JP2024061724A - Heterocyclic compounds - Google Patents

Abstract

[Problem] To provide a novel heterocyclic compound. In particular, to provide a novel heterocyclic compound capable of improving the element characteristics of a light-emitting element. [Solution] The heterocyclic compound is represented by the following general formula (G1), in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded via a substituted or unsubstituted arylene group. JPEG2024061724000077.jpg27167 (In the formula, DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group. In addition, when the arylene groups represented by Ar1 and Ar2 have substituents, the substituents may be bonded to each other to form a ring.) [Selected Figure] None

Description

One aspect of the present invention relates to an object, a method, or a manufacturing method. Alternatively, the present invention relates to a process, a machine, a manufacture, or a composition of matter. In particular, one aspect of the present invention relates to a semiconductor device, a light-emitting device, a display device, a lighting device, a light-emitting element,
Another embodiment of the present invention relates to a heterocyclic compound and a novel synthesis method thereof. Another embodiment of the present invention relates to a light-emitting element, a light-emitting device, an electronic device, and a lighting device each using the heterocyclic compound. Note that one embodiment of the present invention is not limited to the above technical fields.

Light-emitting elements using organic compounds as light emitters, which have characteristics such as thinness, light weight, high-speed response, and low-voltage direct current operation, are expected to be applied to next-generation flat panel displays. In particular, display devices in which light-emitting elements are arranged in a matrix are considered to have an advantage over conventional liquid crystal display devices in that they have a wider viewing angle and better visibility.

The light-emitting mechanism of a light-emitting element is said to be that, by applying a voltage to an EL layer containing a light-emitting body between a pair of electrodes, electrons injected from the cathode and holes injected from the anode recombine at the luminescence center of the EL layer to form molecular excitons, which release energy when relaxing to the ground state, resulting in light emission. Singlet excitation and triplet excitation are known as excited states, and it is believed that light emission is possible through either excited state.

In such light-emitting elements, organic compounds are mainly used in the EL layer, which has a significant impact on improving the element characteristics of the light-emitting element, and therefore various new organic compounds are being developed (see, for example, Patent Document 1).

JP 2007-189001 A

The compound having a dibenzo[f,h]quinoxaline ring reported in the above-mentioned Patent Document 1 has a problem that it is easily crystallized because it has a planar structure. A light-emitting element using a compound that is easily crystallized has a short life. In addition, when another skeleton is directly bonded to the dibenzo[f,h]quinoxaline ring in order to obtain a compound with a three-dimensionally bulky structure, the conjugated system may be expanded, causing a decrease in triplet excitation energy. When the triplet excitation energy is decreased, the luminous efficiency is decreased, and the element characteristics of a light-emitting element using such a compound are also decreased.

Thus, one embodiment of the present invention provides a novel heterocyclic compound. In particular, a novel heterocyclic compound capable of improving the element characteristics of a light-emitting element is provided. Another embodiment of the present invention provides a novel heterocyclic compound having good luminous efficiency and heat resistance. Another embodiment of the present invention provides a novel heterocyclic compound that can be used in a light-emitting element. Another embodiment of the present invention provides a novel heterocyclic compound that can be used in an EL layer of a light-emitting element. In particular, a light-emitting element with high heat resistance, high luminous efficiency and low power consumption, and a light-emitting element with a long lifetime can be provided. Another embodiment of the present invention provides a novel light-emitting element. Another embodiment of the present invention provides a novel light-emitting element.
To provide a novel light-emitting device, a novel electronic device, or a novel lighting device. Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily need to solve all of these problems. Note that problems other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract problems other than these from the description in the specification, drawings, claims, etc.

One embodiment of the present invention is a heterocyclic compound in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded via a substituted or unsubstituted arylene group.

One embodiment of the present invention is a heterocyclic compound represented by the following general formula (G1):

In the general formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group.
When the arylene groups represented by ^r1 and ^Ar2 have substituents, the substituents may be bonded to each other to form a ring.

Another embodiment of the present invention is a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group having ⁶ carbon atoms in General Formula (G1),
n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group. Among the carbons not constituting the furan ring in the benzobisbenzofuranyl group, any one of the carbons adjacent to the carbon bonded to the oxygen of the furan ring is bonded to Ar ^2. In addition, when the arylene groups represented by Ar ¹ and Ar ² have substituents, the substituents may be bonded to each other to form a ring.

Another embodiment of the present invention is a heterocyclic compound represented by the following general formula (G2):

In the general formula (G2), A represents a substituted or unsubstituted benzobisbenzofuranyl group, and R ¹ to R ⁹ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a substituted or unsubstituted benzobisbenzofuranyl group having 6 to 8 carbon atoms.
Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms. When the arylene groups represented by Ar ¹ and Ar ² have substituents, the substituents may be bonded to each other to form a ring.

In the above structure, Ar ² in general formula (G1) or general formula (G2) represents a substituted or unsubstituted phenylene group or a substituted or unsubstituted biphenyldiyl group,
Characteristically, n is 0.

In the above structure, Ar ² in the general formula (G1) or (G2) is a substituted or unsubstituted m-phenylene group or a substituted or unsubstituted biphenyl-3,3′-
It is characterized in that it represents a diyl group, and n is 0.

In each of the above structures, A in general formula (G1) or general formula (G2) is any one of the following general formulae (A1) to (A3), and in general formulae (A1) to (A3), among the carbons not constituting a furan ring, any one of the carbons adjacent to the carbon bonded to oxygen in the furan ring is bonded to ^Ar2 .

However, in the general formulae (A1) to (A3), the benzene ring may have a substituent, and the substituent is a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 7 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms,
Either:

Another embodiment of the present invention is a heterocyclic compound represented by the following structural formula (101), (107), (149), or (150).

The heterocyclic compound of one embodiment of the present invention described above has a high T1 level and can therefore be used as a host material which can be combined with a light-emitting substance (dopant) such as a phosphorescent material.

In addition, the heterocyclic compound of one embodiment of the present invention is a material with high electron transporting properties. Therefore, the heterocyclic compound can be applied to an electron transporting layer and the like in addition to the light-emitting layer of the EL layer of the light-emitting element. Furthermore, the heterocyclic compound of one embodiment of the present invention is a light-emitting substance. Therefore, the heterocyclic compound can be used not only as a host material used in combination with a light-emitting substance such as a phosphorescent material in the light-emitting layer, but also as a light-emitting substance. Therefore, a light-emitting element using the heterocyclic compound of one embodiment of the present invention is included in one embodiment of the present invention.

That is, another embodiment of the present invention is a light-emitting element using a heterocyclic compound in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded to each other through a substituted or unsubstituted arylene group.

Another embodiment of the present invention is a light-emitting element using a heterocyclic compound, in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded to each other via a substituted or unsubstituted arylene group, and any one of carbons that is not constituting a furan ring in the benzobisbenzofuranyl group and is adjacent to a carbon bonded to oxygen in the furan ring is bonded to the arylene group.

In each of the above structures, the light-emitting element has a light-emitting layer, and the light-emitting layer contains the heterocyclic compound and
and a luminescent material.

One embodiment of the present invention includes not only a light-emitting device having a light-emitting element, but also a lighting device having a light-emitting device. Therefore, the light-emitting device in this specification refers to an image display device or a light source (including a lighting device). In addition, a connector, for example, an FP
C (Flexible printed circuit) or TCP (Tape
A module with a carrier package attached, a module with a printed wiring board provided at the end of the TCP, or a module with a COG (Chip On Glass)
The light emitting device also includes any module in which an IC (integrated circuit) is directly mounted using the LED light emitting diode (LED) mounting method.

In one embodiment of the present invention, a novel heterocyclic compound can be provided. In particular, a novel heterocyclic compound that can improve the element characteristics of a light-emitting element can be provided. In addition, in one embodiment of the present invention, a novel heterocyclic compound that has good emission efficiency and heat resistance can be provided. In addition, in one embodiment of the present invention, a novel heterocyclic compound that can be used in a light-emitting element can be provided. In addition, in one embodiment of the present invention, a novel heterocyclic compound that can be used in an EL layer of a light-emitting element can be provided. In particular, a light-emitting element with high heat resistance, a light-emitting element with high emission efficiency and low power consumption, and a light-emitting element with a long lifetime can be provided. In addition,
According to one embodiment of the present invention, a novel light-emitting element can be provided.
It is possible to provide a novel electronic device or a novel lighting device.

1A to 1C are diagrams illustrating a structure of a light-emitting element. 1A to 1C are diagrams illustrating a structure of a light-emitting element. 1A and 1B are diagrams illustrating a light-emitting device. 1A and 1B are diagrams illustrating a light-emitting device. 1A to 1C are diagrams illustrating electronic devices. 1A to 1C are diagrams illustrating electronic devices. FIG. 1A and 1B are diagrams illustrating a lighting device. 1A and 1B are diagrams illustrating a lighting device. FIG. 2 is a diagram showing an example of a touch panel. FIG. 2 is a diagram showing an example of a touch panel. FIG. 2 is a diagram showing an example of a touch panel. 1A and 1B are a block diagram and a timing chart of a touch sensor. Circuit diagram of a touch sensor. ¹ H-NMR chart of the heterocyclic compound represented by structural formula (101). The ultraviolet/visible absorption spectrum and emission spectrum of the heterocyclic compound represented by the structural formula (101). ¹ H-NMR chart of the heterocyclic compound represented by structural formula (107). The ultraviolet/visible absorption spectrum and emission spectrum of the heterocyclic compound represented by the structural formula (107). ¹ H-NMR chart of the heterocyclic compound represented by structural formula (149). The ultraviolet/visible absorption spectrum and emission spectrum of the heterocyclic compound represented by the structural formula (149). ¹ H-NMR chart of the heterocyclic compound represented by structural formula (150). The ultraviolet and visible absorption spectrum and emission spectrum of the heterocyclic compound represented by the structural formula (150). 1A to 1C are diagrams illustrating light-emitting elements. FIG. 13 shows current density vs. luminance characteristics of Light-emitting Elements 1 to 4. FIG. 13 shows voltage-luminance characteristics of Light-emitting Elements 1 to 4. FIG. 13 shows luminance vs. current efficiency characteristics of Light-emitting Elements 1 to 4. 13 shows voltage-current characteristics of Light-emitting Elements 1 to 4. 13 shows emission spectra of Light-emitting Elements 1 to 4. 13A to 13C show the reliability of Light-emitting Elements 1 to 4. 13 is a graph showing changes over time in external quantum efficiency characteristics of the light-emitting elements 1 to 3 and the comparative light-emitting element 5. A figure showing the mass spectrum of 2mBbfPDBq. A figure showing the mass spectrum of 2mBbfPDBq.

Hereinafter, the embodiment of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and the form and details can be changed in various ways without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the embodiment shown below.

In addition, the words "film" and "layer" can be interchangeable depending on the case or situation. For example, the term "conductive layer" can be changed to the term "conductive film". Or, for example, the term "insulating film" can be changed to the term "insulating layer".

(Embodiment 1)
In this embodiment, a heterocyclic compound which is one embodiment of the present invention will be described.

The heterocyclic compound described in this embodiment is a heterocyclic compound characterized in that a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded to each other via a substituted or unsubstituted arylene group.

It is generally known that by increasing the number of fused rings forming the molecular structure of an organic compound, the heat resistance of an organic compound having a structure with a larger number of fused rings increases as the molecular weight increases, and a longer life can be expected when used in a light-emitting element. However, simply increasing the number of fused rings results in a molecular structure with higher planarity, which leads to problems such as a decrease in heat resistance due to the tendency of a thin film of the organic compound to crystallize, a decrease in the triplet excitation level (T1 level) of the compound, and further a decrease in the solubility of the compound, making it difficult to synthesize and purify the compound. In contrast, the heterocyclic compound according to one embodiment of the present invention can provide a compound having a high T1 level by expanding the skeleton of the organic molecule using a fused ring containing a heteroatom. In addition, a highly planar dibenzo[f,h]quinoxalinyl group and a benzobisbenzofuranyl group are bonded via an arylene group to form a bulky compound, which can suppress crystallization and improve heat resistance. Therefore, the heterocyclic compound described in this embodiment is represented by the following general formula (
G1).

In general formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group.
When the arylene groups represented by ^r1 and ^Ar2 have substituents, the substituents may be bonded to each other to form a ring.

In addition, in another embodiment, in the heterocyclic compound represented by the general formula (G1),
represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar
² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group. Among the carbons not constituting the furan ring of the benzobisbenzofuranyl group, any one of the carbons adjacent to the carbon bonded to the oxygen of the furan ring is bonded to Ar ^2. In addition, when the arylene groups represented by Ar ¹ and Ar ² have substituents, the substituents may be bonded to each other to form a ring.

Examples of the arylene group having 6 to 13 carbon atoms represented by Ar ¹ or Ar ² in general formula (G1) include a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthalenediyl group, a substituted or unsubstituted biphenyldiyl group, a substituted or unsubstituted fluorenediyl group, and the like. More specific examples include arylene groups represented by the following structural formulas (α1) to (α15), and the like.

In addition, in the general formula (G1), of the substituted or unsubstituted benzobisbenzofuranyl group represented by A, the unsubstituted benzobisbenzofuranyl group is any one of the following general formulae (A1) to (A7).

In addition, in the case where the benzobisbenzofuranyl group represented by A in the general formula (G1) has a substituent, the benzene ring in the general formulae (A1) to (A7) may have a substituent, and examples of the substituent include a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 7 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 13 carbon atoms.

In addition, specific examples of the alkyl group having 1 to 6 carbon atoms as a substituent in the general formulae (A1) to (A7) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a s
ec-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, s
ec-pentyl group, tert-pentyl group, neopentyl group, hexyl group, isohexyl group, sec-hexyl group, tert-hexyl group, neohexyl group, 3-methylpentyl group, 2-methylpentyl group, 2-ethylbutyl group, 1,2-dimethylbutyl group, 2,3-
Examples thereof include a dimethylbutyl group.

When the general formulae (A1) to (A7) each have a cycloalkyl group having 5 to 7 carbon atoms as a substituent, specific examples thereof include a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.

Furthermore, when the general formulae (A1) to (A7) have an aryl group having 6 to 13 carbon atoms as a substituent, specific examples thereof include a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, and an indenyl group.

The substitution in the general formula (G1) is preferably a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group,
An alkyl group having 1 to 6 carbon atoms, such as an n-hexyl group, a phenyl group, an o-tolyl group, an m-
It represents that the fluorene-diyl group has a substituent such as an aryl group having 6 to 12 carbon atoms, such as a tolyl group, a p-tolyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenyl group, a 3-biphenyl group, or a 4-biphenyl group. In addition, these substituents may be bonded to each other to form a ring. For example, when the fluorene-diyl group, which is an arylene group, is a 9,9-diphenyl-9H-fluorene-2,7-diyl group having two phenyl groups at the 9-position as substituents, the phenyl groups may be bonded to each other to form a spiro-9,9'-bifluorene-2,7-diyl group.

Another example of the heterocyclic compound of one embodiment of the present invention is a heterocyclic compound having a structure represented by General Formula (G2) below.

In formula (G2), A represents a substituted or unsubstituted benzobisbenzofuranyl group, and R ¹ to R ⁹ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted benzobisbenzofuranyl group having 6 to 6 carbon atoms.
Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms. When the arylene groups represented by Ar ¹ and Ar ² have substituents, the substituents may be bonded to each other to form a ring.

Specific examples of the arylene group having 6 to 13 carbon atoms represented by Ar ¹ or Ar ² in general formula (G2) include arylene groups represented by the following structural formulas (α1) to (α15).

In addition, in the general formula (G2), of the substituted or unsubstituted benzobisbenzofuranyl group represented by A, the unsubstituted benzobisbenzofuranyl group is any one of the following general formulae (A1) to (A7).

In addition, in the case where the benzobisbenzofuranyl group represented by A in the general formula (G2) has a substituent, the benzene ring in the general formulae (A1) to (A7) may have a substituent, and examples of the substituent include a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 7 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 13 carbon atoms.

In addition, specific examples of the alkyl group having 1 to 6 carbon atoms as a substituent in the general formulae (A1) to (A7) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a s
ec-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, s
ec-pentyl group, tert-pentyl group, neopentyl group, hexyl group, isohexyl group, sec-hexyl group, tert-hexyl group, neohexyl group, 3-methylpentyl group, 2-methylpentyl group, 2-ethylbutyl group, 1,2-dimethylbutyl group, 2,3-
Examples thereof include a dimethylbutyl group.

When the general formulae (A1) to (A7) each have a cycloalkyl group having 5 to 7 carbon atoms as a substituent, specific examples thereof include a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.

Furthermore, when the general formulae (A1) to (A7) have an aryl group having 6 to 13 carbon atoms as a substituent, specific examples thereof include a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, and an indenyl group.

Specific examples of the alkyl group having 1 to 6 carbon atoms for R ¹ to R ⁹ in the general formula (G2) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group,
Examples of such alkyl groups include an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, a neohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, and a 2,3-dimethylbutyl group.

Specific examples of the aryl group having 6 to 13 carbon atoms for R ¹ to R ⁹ in general formula (G2) include a phenyl group, a biphenyl group, a tolyl group, a naphthyl group, a xylyl group, a fluorenyl group, and an indenyl group.

The substitution in the general formula (G2) is preferably a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group,
An alkyl group having 1 to 6 carbon atoms, such as an n-hexyl group, a phenyl group, an o-tolyl group, an m-
It represents that the fluorene-diyl group has a substituent such as an aryl group having 6 to 12 carbon atoms, such as a tolyl group, a p-tolyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenyl group, a 3-biphenyl group, or a 4-biphenyl group. In addition, these substituents may be bonded to each other to form a ring. For example, when the fluorene-diyl group, which is an arylene group, is a 9,9-diphenyl-9H-fluorene-2,7-diyl group having two phenyl groups at the 9-position as substituents, the phenyl groups may be bonded to each other to form a spiro-9,9'-bifluorene-2,7-diyl group.

Next, specific structural formulae of the heterocyclic compound according to one embodiment of the present invention will be shown below, but the present invention is not limited thereto.

The heterocyclic compounds represented by the above structural formulas (101) to (184) and (201) to (400) are examples included in the heterocyclic compounds represented by the above general formulas (G1) and (G2),
The heterocyclic compound according to one embodiment of the present invention is not limited to these.

Next, an example of a method for synthesizing a heterocyclic compound represented by the following general formula (G1), which is one embodiment of the present invention, will be described. Note that various reactions can be applied as a method for synthesizing an organic compound represented by the general formula (G1). For example, a compound represented by the general formula (G1) can be synthesized by the method shown below.
However, an organic compound represented by the general formula (
The synthesis method of the organic compound represented by G1) is not limited to the following synthesis method.

In general formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group.
When the arylene group represented by ^r1 and ^Ar2 has a substituent, the substituent may be bonded to each other to form a ring. In addition, among the carbons not constituting the furan ring of the benzobisbenzofuranyl group, any one of the carbons adjacent to the carbon bonded to the oxygen of the furan ring may be bonded to ^Ar2 .

A synthesis scheme (A) of the heterocyclic compound represented by the general formula (G1) is shown below. As shown in the synthesis scheme (A), the heterocyclic compound represented by the general formula (G1) can be synthesized by coupling a dibenzo[f,h]quinoxaline compound (compound 1) with a benzobisbenzofuran compound (compound 2).

In the synthetic scheme (A), DBq is a substituted or unsubstituted dibenzo[f,h
]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms,
A represents a substituted or unsubstituted benzobisbenzofuranyl group. When the arylene groups represented by Ar ¹ and Ar ² each have a substituent, the substituents may be bonded to each other to form a ring.

In addition, in the case of carrying out the Suzuki-Miyaura coupling reaction using a palladium catalyst in the synthesis scheme (A), ^X1 and ^X2 represent a halogen group, a boronic acid group, an organic boron group, or a triflate group, and the halogen group is preferably iodine, bromine, or chlorine. In addition, in the reaction, bis(dibenzylideneacetone)palladium(0), palladium acetate(II),
Palladium compounds such as [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride and tetrakis(triphenylphosphine)palladium(0) and ligands such as tri(tert-butyl)phosphine, tri(n-hexyl)phosphine, tricyclohexylphosphine, di(1-adamantyl)-n-butylphosphine, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl and tri(ortho-tolyl)phosphine can be used.

In the reaction shown in the synthesis scheme (A), an organic base such as sodium tert-butoxide, or an inorganic base such as potassium carbonate, cesium carbonate, or sodium carbonate can be used. Furthermore, as a solvent, toluene, xylene, benzene, tetrahydrofuran, dioxane, ethanol, methanol, water, or the like can be used. However, the reagents that can be used are not limited to the above-mentioned reagents.

In addition, the reaction in the synthetic scheme (A) is not limited to the Suzuki-Miyaura coupling reaction, and may be, for example, a Migita-Kosugi-Stille coupling reaction using an organotin compound, a Kumada-Tamao-Corleau coupling reaction using a Grignard reagent, a Negishi coupling reaction using an organozinc compound, or a reaction using copper or a copper compound.

In the synthesis scheme (A), when the Migita-Kosugi-Stille coupling reaction is used, X
Either ^X1 or ^X2 represents an organic tin group, and the other represents a halogen group. That is,
Either compound 1 or compound 2 represents an organotin compound.

In the synthesis scheme (A), when the Kumada-Tamao-Corleau coupling reaction is used, X
Either ^X1 or ^X2 represents a magnesium halide group, and the other represents a halogen group. That is, either Compound 1 or Compound 2 represents a Grignard reagent.

In the synthesis scheme (A), when the Negishi coupling reaction is used, one of ^X1 and ^X2 represents an organic zinc group, and the other represents a halogen group. That is, one of compound 1 and compound 2 represents an organic zinc compound.

In the synthesis of the organic compound (G1) of the present invention, the synthesis method is not limited to the synthesis scheme (A).

Although an example of a method for synthesizing a heterocyclic compound has been described above as one embodiment of the present invention, the present invention is not limited thereto, and the heterocyclic compound may be synthesized by other synthesis methods.

Since the heterocyclic compound according to one embodiment of the present invention has electron-transporting and hole-transporting properties, it can be used as a host material for a light-emitting layer, or for an electron-transporting layer or a hole-transporting layer. Since the heterocyclic compound has a high T1 level, it is preferable to use the heterocyclic compound as a host material in combination with a substance that emits phosphorescence (phosphorescent material). Since the heterocyclic compound exhibits fluorescent emission, it can be used as a light-emitting substance for a light-emitting element by itself. Therefore, light-emitting elements including these heterocyclic compounds are also included in one embodiment of the present invention.

By using the heterocyclic compound according to one embodiment of the present invention, a light-emitting element, a light-emitting device, an electronic device, or a lighting device with high emission efficiency can be realized. In addition, a light-emitting element, a light-emitting device, an electronic device, or a lighting device with low power consumption can be realized.

Note that one embodiment of the present invention has been described in this embodiment. In addition, one embodiment of the present invention will be described in another embodiment. However, one embodiment of the present invention is not limited thereto. In other words, since various embodiments of the present invention are described in this embodiment and the other embodiments, one embodiment of the present invention is not limited to a specific embodiment. For example, although an example of application to a light-emitting element has been described as one embodiment of the present invention, one embodiment of the present invention is not limited thereto.
Depending on the situation, one embodiment of the present invention may be applied to devices other than light-emitting elements.
Depending on the situation, one embodiment of the present invention does not necessarily need to be applied to a light-emitting element.

The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiment modes.

(Embodiment 2)
In this embodiment, a light-emitting element which is one embodiment of the present invention will be described with reference to FIGS.

The light-emitting element shown in this embodiment has a pair of electrodes (a first electrode (anode) 101 and a second electrode (
The EL layer 102 including the light-emitting layer 113 is sandwiched between the cathode 103 and the cathode 104. The EL layer 102 is
In addition to the light-emitting layer 113, the light-emitting element 110 includes a hole injection layer 111, a hole transport layer 112, an electron transport layer 114, an electron injection layer 115, and the like.

When a voltage is applied to such a light-emitting element, holes injected from the first electrode 101 side and electrons injected from the second electrode 103 side recombine in the light-emitting layer 113, and the energy generated thereby causes a light-emitting substance such as an organometallic complex contained in the light-emitting layer 113 to emit light.

The hole injection layer 111 in the EL layer 102 is a hole transport layer 112 or a light emitting layer 113.
The hole injection layer 111 is a layer capable of injecting holes into the light-emitting layer 113, and can be formed of, for example, a substance having a high hole transporting property and an acceptor substance. In this case, holes are generated when electrons are extracted from the substance having a high hole transporting property by the acceptor substance. Therefore, holes are injected from the hole injection layer 111 to the light-emitting layer 113 through the hole transport layer 112. Note that a substance having a high hole injection property can also be used for the hole injection layer 111. For example, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, or the like can be used. In addition, phthalocyanine-based compounds such as phthalocyanine (abbreviation: H ₂ Pc) and copper phthalocyanine (CuPC), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'
The hole injection layer 111 can also be formed from an aromatic amine compound such as N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD) or a polymer such as poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonic acid) (abbreviation: PEDOT/PSS).

The following describes a specific example of how to fabricate the light-emitting element shown in this embodiment.

The first electrode (anode) 101 and the second electrode (cathode) 103 can be made of a metal, an alloy, an electrically conductive compound, or a mixture thereof. Specifically, indium oxide-tin oxide, indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, etc.
ide), indium oxide containing tungsten oxide and zinc oxide, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo
), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti)
In addition to the above, elements belonging to Group 1 or 2 of the periodic table, namely, alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as calcium (Ca) and strontium (Sr), magnesium (Mg), and alloys containing these (MgAg, Al
Examples of the material that can be used include rare earth metals such as lithium (Li), europium (Eu), and ytterbium (Yb), alloys containing these metals, and graphene compounds such as graphene and graphene oxide. The first electrode (anode) 101 and the second electrode (cathode) 103 can be formed by, for example, a sputtering method or a deposition method (including a vacuum deposition method).

The hole-transporting material having a high hole-transporting property used in the hole-injection layer 111 and the hole-transporting layer 112 may be an aromatic amine compound, a carbazole derivative, an aromatic hydrocarbon, a polymer compound (oligomer,
Various organic compounds such as organic compounds having a hole transporting property (e.g., dendrimer, polymer, etc.) can be used. Specifically, a substance having a hole mobility of 1×10 ⁻⁶ cm ² /Vs or more is preferable. In addition, a layer formed using a substance with high hole transporting property may be not only a single layer but also a laminate of two or more layers. Specific organic compounds that can be used as a substance with hole transporting property are listed below.

For example, the aromatic amine compound includes N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), DN
TPD, 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4',4''-tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA), 4,4',4''-tris(N,N-diphenylamino)
Triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,
Examples of the compound include 4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB).

Specific examples of carbazole derivatives include 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPC
A1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), etc.
carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 1,4-bis[4-
(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene and the like can be used.

Examples of aromatic hydrocarbons include 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2
-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert-butyl-9,1
0-Bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-
naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1
-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9'-bianthryl, 10,10'-diphenyl-9,9'-bianthryl, 10,10'-bis(2-phenylphenyl)-9,9'-bianthryl,
10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-
Examples of suitable aromatic hydrocarbons include bianthryl, anthracene, tetracene, rubrene, perylene, and 2,5,8,11-tetra(tert-butyl)perylene. In addition, pentacene, coronene, and the like can also be used. In this way, it is more preferable to use aromatic hydrocarbons having a hole mobility of 1×10 ⁻⁶ cm ² /Vs or more and having 14 to 42 carbon atoms. The aromatic hydrocarbon may have a vinyl skeleton. An example of an aromatic hydrocarbon having a vinyl group is 4,4′-bis(2,2-diphenylvinyl)biphenyl (abbreviation: D
PVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA), and the like.

Furthermore, poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation:
Alternatively, polymer compounds such as poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD) can be used.

Acceptor substances used in the hole injection layer 111 and the hole transport layer 112 include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F ₄ -TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4
Examples of the compound include compounds having an electron-withdrawing group (a halogen group or a cyano group), such as 5,8,9,12-hexaazatriphenylene (HAT-CN). In particular, compounds in which an electron-withdrawing group is bonded to a condensed aromatic ring having a plurality of heteroatoms, such as HAT-CN, are thermally stable and preferable. Examples of the compound include oxides of metals belonging to Groups 4 to 8 of the periodic table. Specific examples include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide,
Molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide are preferred because they have high electron accepting properties, and among these, molybdenum oxide is particularly preferred because it is stable in the air, has low hygroscopicity, and is easy to handle.

The light-emitting layer 113 is a layer including a light-emitting substance. Examples of the light-emitting substance include a fluorescent light-emitting substance and a phosphorescent light-emitting substance. Specifically, an organometallic complex is used as the phosphorescent light-emitting substance. When an organometallic complex (guest material) is used in the light-emitting layer 113, it is preferable to include a substance having a higher triplet excitation energy than the organometallic complex as a host material. In addition to the light-emitting substance, the light-emitting layer 113 may include two types of organic compounds (which may be any of the above host materials) that are combined to form an exciplex (also called an exciplex) when carriers (electrons and holes) in the light-emitting layer 113 are recombined. In order to efficiently form an exciplex, it is particularly preferable to combine a compound that easily receives electrons (a material having electron transport properties) and a compound that easily receives holes (a material having hole transport properties). In this way, when a material having electron transport properties and a material having hole transport properties are combined to form a host material that forms an exciplex, the carrier balance of holes and electrons in the light-emitting layer can be easily optimized by adjusting the mixing ratio of the material having electron transport properties and the material having hole transport properties. By optimizing the carrier balance between holes and electrons in the light-emitting layer,
It is possible to prevent the recombination of electrons and holes from occurring in a biased region in the light-emitting layer, and by preventing the recombination from occurring in a biased region, it is possible to improve the reliability of the light-emitting device.

In addition, a compound that is easy to accept electrons and is preferably used for forming the above exciplex (
Examples of the electron transporting material include π-electron deficient heteroaromatic compounds such as nitrogen-containing heteroaromatic compounds and metal complexes. Specifically, bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq ₂ ), bis(2-methyl-8
-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq
), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), and other metal complexes,
(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD),
rt-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[
5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2''
-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-
Heterocyclic compounds having a polyazole skeleton such as phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-
(Dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazole-9-
2mCzBPD
Bq), 2-[4-(3,6-diphenyl-9H-carbazol-9-yl)phenyl]
Dibenzo[f,h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mD
BTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]
Dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 4,6-bis[
3-(Phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm
), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6
heterocyclic compounds having a diazine skeleton such as 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm-II), 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), heterocyclic compounds having a triazine skeleton such as 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), and 3,5-bis[
3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy)
, 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB)
Among the above, heterocyclic compounds having a diazine skeleton and a triazine skeleton and heterocyclic compounds having a pyridine skeleton are preferred because of their high reliability. In particular, heterocyclic compounds having a diazine (pyrimidine or pyrazine) skeleton and a triazine skeleton have high electron transport properties and contribute to reducing the driving voltage.

In addition, a compound that is easy to accept holes and is preferable for use in forming the above exciplex (
As the hole transporting material, a π-electron rich heteroaromatic compound (for example, a carbazole derivative or an indole derivative) or an aromatic amine can be suitably used.
9,9'-Bifluorene (abbreviation: PCASF), 4,4',4''-tris[N-(1-
naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1'-TNATA), 2
,7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-
9,9'-Bifluorene (abbreviation: DPA2SF), N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA
2B), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPNF), N,N',N''-triphenyl-N,N',
N''-tris(9-phenylcarbazol-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPASF), N,N'-bis[4
-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), NPB, N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), BSPB, 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPA
FLP), N-(9,9-dimethyl-9H-fluoren-2-yl)-N-{9,9-dimethyl-2-[N'-phenyl-N'-(9,9-dimethyl-9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine (abbreviation: DFLADFL)
, PCzPCA1, 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation:
PCzDPA2), DNTPD, 3,6-bis[N-(4-diphenylaminophenyl)
-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2)
, PCzPCA2, 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(
9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi
1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4'
'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PC
BNBB), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 9,9-dimethyl-
N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]
Fluorene-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluorene-2-
Amine (abbreviation: PCBASF), N-(4-biphenyl)-N-(9,9-dimethyl-9
H-fluoren-2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation:
PCBiF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-
9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2
Compounds with aromatic amine skeletons such as PCBBiF, 1,3-bis(N-carbazolyl)benzene (mCP), CBP, 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (CzTP), 9-phenyl-9
H-3-(9-phenyl-9H-carbazol-3-yl)carbazole (abbreviation: PCC
P) and other compounds with a carbazole skeleton, such as 4,4',4''-(benzene-1,3
,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP
-IV) and 4,4',4''-(benzene-1,
3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[
Examples of compounds having a furan skeleton include compounds having a furan skeleton such as 3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II).
Among the above, compounds having an aromatic amine skeleton and compounds having a carbazole skeleton are preferable because they have good reliability, high hole transport properties, and contribute to reducing the driving voltage.

Note that by forming the light-emitting layer 113 so as to contain the above-described organometallic complex (guest material) and a host material, the light-emitting layer 113 can emit phosphorescent light with high luminous efficiency.

In addition, the light-emitting layer 113 is not limited to the single-layer structure shown in FIG.
The light emitting layer 113 may have a laminated structure of two or more layers as shown in FIG. 1B. In this case, however, each of the laminated layers is required to emit light. For example, the first light emitting layer 113 (a1
) is configured to emit fluorescent light, and the second light-emitting layer 113 (a
2) may be configured to emit phosphorescence. The stacking order may be reversed. In addition, in the layer from which phosphorescence is obtained, it is preferable to configure the layer to emit light by energy transfer from the exciplex to the dopant. In addition, the color of the emitted light may be the same or different from the color of the emitted light from one layer, but when they are different, for example, one layer may be configured to emit blue light, and the other layer may be configured to emit orange light or yellow light. In addition, each layer may be configured to contain multiple types of dopants.

In addition, when the light-emitting layer 113 has a stacked structure, a light-emitting substance that converts singlet excitation energy into light emission, a light-emitting substance that converts triplet excitation energy into light emission, or the like can be used alone or in combination. In this case, for example, the following can be used.

Examples of luminescent substances that convert singlet excitation energy into luminescence include fluorescent substances (fluorescent compounds).

The fluorescent substance is N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S).
, 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)
Triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4
'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAP
PA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,1
1-Tetra(tert-butyl)perylene (abbreviation: TBP), 4-(10-phenyl-9
-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9
,10-diyldi-4,1-phenylene)bis[N,N',N'-triphenyl-1,4
-phenylenediamine] (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9
,10-diphenyl-2-anthryl)phenyl]-9H-carbazol-3-amine (
Abbreviation: 2PAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (Abbreviation: 2DPAP)
PA), N,N,N',N',N'',N'',N',N'''-Octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9
H-carbazol-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1
'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DP
APA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABP
hA), 9,10-bis(1,1'-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2Y
GABPhA), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhA
PhA), Coumarin 545T, N,N'-diphenylquinacridone, (abbreviation: DPQd)
, rubrene, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]
ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: D
CM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H
-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a
]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-
1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-
[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-
benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation:
BisDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDC
JTM) and others.

Examples of luminescent substances that convert triplet excitation energy into luminescence include substances that emit phosphorescence (phosphorescent compounds) and TADF materials (thermally activated delayed fluorescence compounds) that exhibit thermally activated delayed fluorescence (TADF). Note that the delayed fluorescence in TADF materials refers to luminescence that has a spectrum similar to that of normal fluorescence but has a significantly long lifespan. The lifespan is 1×10 ⁻⁶ seconds or more, preferably 1×10 ⁻³ seconds or more.

The phosphorescent material is bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C ^2' }iridium(III) picolinate (abbreviation: [Ir(C
F ₃ ppy) ₂ (pic)]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C ^{2 '} ]iridium(III) acetylacetonate (abbreviation: FIracac
), tris(2-phenylpyridinato)iridium(III) (abbreviation: [Ir(ppy)
₃ ]), bis(2-phenylpyridinato)iridium(III) acetylacetonate (
abbreviation: [Ir(ppy) ₂ (acac)]), tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac) ₃ (Phen)]),
Bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: [
Ir(bzq) ₂ (acac)]), bis(2,4-diphenyl-1,3-oxazolato-N,C ^2′ )iridium(III) acetylacetonate (abbreviation: [Ir(dpo) ₂
(acac)]), bis{2-[4'-(perfluorophenyl)phenyl]pyridinato-N,C ^2' }iridium(III) acetylacetonate (abbreviation: [Ir(p-PF-
bis( ₂ -phenylbenzothiazolato-N,C ^2′ )iridium(III) acetylacetonate (abbreviation: [Ir(bt) ₂ (acac)]), bis[2-(2′-benzo[4,5-α]thienyl)pyridinato-N,C ^3′ ]iridium (
III) Acetylacetonate (abbreviation: [Ir(btp) ₂ (acac)]), bis(1
-phenylisoquinolinato-N,C ^2' )iridium(III) acetylacetonate (
abbreviation: [Ir(piq) ₂ (acac)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(F
(acetylacetonato)bis(3,5 _{-dimethyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me) 2 (} acac)])
c)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-iPr) ₂ (acac)
]), (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: [Ir(tppr) ₂ (acac)]), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(t
ppr) ₂ (dpm)]), (acetylacetonato)bis(6-tert-butyl-4-
Phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) ₂ (ac
ac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) ₂ (acac)]), 2,3,7,8,12,
13,17,18-Octaethyl-21H,23H-porphyrin platinum(II) (abbreviation:
PtOEP), tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM) ₃ (Phen)]), tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA) ₃ (Phen)]), and the like.

Examples of TADF materials include fullerene and its derivatives, acridine derivatives such as proflavine, and eosin.
Examples of the metal-containing porphyrin include metal-containing porphyrins containing cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), etc. Examples of the metal-containing porphyrin include protoporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Protoporphyrin-tin fluoride complex)).
IX)), mesoporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Meso IX)),
Hematoporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (abbreviation: SnF ₂ (Copro
III-4Me), octaethylporphyrin-tin fluoride complex (abbreviation: SnF ₂ (O
EP), etioporphyrin-tin fluoride complex (abbreviation: SnF ₂ (Etio I)),
Octaethylporphyrin-platinum chloride complex (abbreviation: PtCl ₂ OEP) is an example.
Furthermore, 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,
3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ
It is also possible to use a heterocyclic compound having a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, such as the above-mentioned heterocyclic compounds. Note that a substance in which a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring are directly bonded is particularly preferred, since the donor property of the π-electron rich heteroaromatic ring and the acceptor property of the π-electron deficient heteroaromatic ring are both strong, and the energy difference between S1 and T1 is small.

The electron transport layer 114 is _a layer containing a substance having a high electron transporting property (also called an electron transporting compound).
), tris(4-methyl-8-quinolinolato)aluminum (abbreviation: Almq ₃ ), Be
Bq ₂ , BAlq, bis[2-(2-hydroxyphenyl)benzoxazolato]zinc (
Abbreviation: Zn(BOX) ₂ ), bis[2-(2-hydroxyphenyl)benzothiazolato]
A metal complex such as zinc (abbreviation: Zn(BTZ) ₂ ) can be used.
OXD-7, TAZ, 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ)
, Bathophenanthroline (abbreviation: Bphen), Bathocuproine (abbreviation: BCP), 4
, 4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs
Heteroaromatic compounds such as poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co
-(pyridine-3,5-diyl)] (abbreviation: PF-Py), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)]
A polymer compound such as PF-BPy (abbreviation) can also be used. The substances described here are mainly substances having an electron mobility of 1×10 ⁻⁶ cm ² /Vs or more. Note that substances other than those described above may also be used for the electron transport layer 114 as long as they have a higher electron transport property than a hole transport property.

The electron transport layer 114 may have not only a single layer structure, but also a stacked structure of two or more layers made of the above substances.

The electron injection layer 115 is a layer containing a substance having a high electron injection property. The electron injection layer 115 may contain any of a variety of substances, including lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ₂ ),
Alkali metals such as lithium oxide (LiOx), alkaline earth metals, or compounds thereof can be used. Rare earth metal compounds such as erbium fluoride (ErF ₃ ) can also be used. Electrides may also be used for the electron injection layer 115. Examples of the electrides include a substance in which electrons are highly concentrated in a mixed oxide of calcium and aluminum. The above-mentioned substances constituting the electron transport layer 114 can also be used.

Alternatively, a composite material obtained by mixing an organic compound and an electron donor (donor) may be used for the electron injection layer 115. Such a composite material has excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound may be:
A material having excellent transport properties for the generated electrons is preferable, and specifically, for example, the above-mentioned substances constituting the electron transport layer 114 (metal complexes, heteroaromatic compounds, etc.) can be used. The electron donor may be any substance that exhibits electron donating properties to the organic compound. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferable, and examples thereof include lithium, cesium, magnesium, calcium, erbium, and ytterbium. In addition, alkali metal oxides and alkaline earth metal oxides are preferable, and examples thereof include lithium oxide, calcium oxide,
Examples of the suitable organic compounds include barium oxide, magnesium oxide, and other Lewis bases, and tetrathiafulvalene (TTF) and other organic compounds.

The hole injection layer 111, the hole transport layer 112, the light emitting layer 113, and the electron transport layer 114
and the electron injection layer 115 can be formed by using a method such as a vapor deposition method (including a vacuum deposition method), a printing method (e.g., letterpress printing, intaglio printing, gravure printing, lithographic printing, stencil printing, etc.), an inkjet method, a coating method, etc., either alone or in combination. In addition to the above-mentioned materials, the hole injection layer 111, the hole transport layer 112, the light-emitting layer 113, the electron transport layer 114, and the electron injection layer 115 may be formed by using an inorganic compound such as a quantum dot or a polymer compound (oligomer, dendrimer, polymer, etc.).

By doing the above, a light-emitting element can be fabricated in which an EL layer is sandwiched between a pair of electrodes.

Note that the structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

(Embodiment 3)
In this embodiment, a light-emitting element having a structure including a plurality of EL layers (hereinafter,
The tandem light emitting device (hereinafter referred to as a tandem light emitting device) will be described.

The light-emitting element shown in this embodiment has a pair of electrodes (first electrode 201) as shown in FIG.
The light emitting element is a tandem type light emitting element having a plurality of EL layers (first EL layer 202(1), second EL layer 202(2)) between a first electrode 202(1) and a second electrode 204) with a charge generating layer 205 interposed therebetween.

In this embodiment, the first electrode 201 functions as an anode, and the second electrode 204 functions as a cathode.
EL layer 202(1) and second EL layer 202(2) may have the same structure as that of the EL layer shown in Embodiment 2. In addition, the multiple EL layers (first EL layer 202(1) and second EL layer 202(2)) may both have the same structure as the EL layer shown in Embodiment 2, or either one of them may have the same structure. In other words, the first EL layer 202(1) and the second EL layer 202(2) may have the same structure or different structures, and when they have the same structure, the embodiment 2 can be applied.

In addition, the charge generation layer 205 provided between the multiple EL layers (the first EL layer 202(1), the second EL layer 202(2)) has a function of injecting electrons into one EL layer and injecting holes into the other EL layer when a voltage is applied between the first electrode 201 and the second electrode 204.
In this embodiment, when a voltage is applied to the first electrode 201 so that the first electrode 201 has a higher potential than the second electrode 204, electrons are injected from the charge generation layer 205 into the first EL layer 202(1), and holes are injected into the second EL layer 202(2).

From the viewpoint of light extraction efficiency, the charge generation layer 205 preferably has a translucency to visible light (specifically, the visible light transmittance of the charge generation layer 205 is 40% or more). The charge generation layer 205 functions even if it has a lower electrical conductivity than the first electrode 201 and the second electrode 204.

The charge generation layer 205 may be a structure in which an electron acceptor is added to an organic compound having a high hole transporting property, or a structure in which an electron donor is added to an organic compound having a high electron transporting property, or a structure in which both of these structures are laminated.

In the case where an electron acceptor is added to an organic compound having a high hole transporting property, the organic compound having a high hole transporting property is the same as that used in the hole injection layer 111 and the hole transport layer 1 in the embodiment 2.
The material shown in 12 as a material with high hole transport properties can be used. For example, N
An aromatic amine compound such as PB, TPD, TDATA, MTDATA, or BSPB can be used. The substances described here are mainly substances having a hole mobility of 1×10 ⁻⁶ cm ² /Vs or more. However, substances other than those described above may be used as long as they are organic compounds that have a higher hole transporting property than electron transporting properties.

Examples of the electron acceptor include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F ₄ -TCNQ), chloranil, etc. Examples of the oxides of metals belonging to Groups 4 to 8 of the periodic table include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide,
Tungsten oxide, manganese oxide, and rhenium oxide are preferred because they have high electron accepting properties, and molybdenum oxide is particularly preferred because it is stable in the air, has low hygroscopicity, and is easy to handle.

On the other hand, in the case where an electron donor is added to an organic compound having high electron transport properties,
As the organic compound with a high electron-transporting property, the substance described in Embodiment 2 as the substance with a high electron-transporting property used for the electron-transporting layer 114 can be used. For example, Alq, _Almq
Metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as _BeBq2 and BAlq, can be used. In addition, metal complexes having an oxazole or thiazole ligand, such as Zn(BOX) ₂ and Zn(BTZ) ₂ , can also be used.
Other than metal complexes, PBD, OXD-7, TAZ, Bphen, BCP, etc. can also be used. The substances described here are mainly substances having an electron mobility of 1×10 ⁻⁶ cm ² /Vs or more. Note that substances other than those described above may also be used as long as they are organic compounds that have a higher electron transporting property than holes.

As the electron donor, an alkali metal, an alkaline earth metal, a rare earth metal, or a metal belonging to Groups 2 and 13 of the periodic table, or an oxide or carbonate thereof can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg),
, calcium (Ca), ytterbium (Yb), indium (In), lithium oxide,
It is preferable to use cesium carbonate, etc. Also, an organic compound such as tetrathianaphthacene may be used as the electron donor.

By forming the charge generating layer 205 using the above-mentioned material, it is possible to suppress an increase in driving voltage when an EL layer is laminated. The charge generating layer 205 can be formed by using a deposition method (including a vacuum deposition method), a printing method (e.g., a letterpress printing method, an intaglio printing method, a gravure printing method, a lithographic printing method, a stencil printing method, etc.), an inkjet method, a coating method, etc., either alone or in combination.

In this embodiment, a light-emitting element having two EL layers has been described; however, as shown in FIG. 2B, the present invention can be similarly applied to a light-emitting element having n (n is 3 or more) stacked EL layers (202(1) to 202(n)). When a plurality of EL layers are provided between a pair of electrodes as in the light-emitting element according to this embodiment, a charge generation layer (205(1) to 205(n-1)) is provided between the EL layers, respectively, to enable light emission in a high luminance region while maintaining a low current density. Since the current density can be maintained low, a long-life element can be realized.

In addition, by making the luminescent color of each EL layer different, it is possible to obtain luminescence of a desired color as a whole light-emitting element. For example, in a light-emitting element having two EL layers,
It is also possible to obtain a light-emitting element that emits white light as a whole by making the emission color of the first EL layer and the emission color of the second EL layer complementary to each other. Note that complementary colors refer to a relationship between colors that become achromatic when mixed. In other words, white light emission can be obtained by mixing lights of complementary colors. Specifically, a combination in which blue light emission is obtained from the first EL layer and yellow or orange light emission is obtained from the second EL layer can be given. In this case,
The blue emission and the yellow emission (or the orange emission) do not need to both be the same fluorescent emission or phosphorescent emission. The blue emission may be fluorescent and the yellow emission (or the orange emission) may be phosphorescent, or vice versa.

The same is true for a light-emitting element having three EL layers. For example, when the emission color of the first EL layer is red, the emission color of the second EL layer is green, and the emission color of the third EL layer is blue, the light-emitting element as a whole can emit white light.

Note that the structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiment modes.

(Embodiment 4)
In this embodiment, a light-emitting device which is one embodiment of the present invention will be described.

The light-emitting device may be a passive matrix light-emitting device or an active matrix light-emitting device. The light-emitting element described in any of the other embodiments can be applied to the light-emitting device shown in this embodiment.

In this embodiment mode, an active matrix light emitting device will be described with reference to FIG.

3A is a top view showing a light emitting device, and FIG. 3B is a top view showing a light emitting device taken along a dashed line A-A in FIG.
1 is a cross-sectional view taken along the line 100 of FIG. 1A. The active matrix light-emitting device has a pixel portion 302, a driver circuit portion (source line driver circuit) 303, and a driver circuit portion (gate line driver circuit) 304 (304a and 304b), which are provided on an element substrate 301. The pixel portion 302, the driver circuit portion 303, and the driver circuit portions 304a and 304b are sealed between the element substrate 301 and a sealing substrate 306 by a sealant 305.

In addition, on the element substrate 301, there are provided wiring 307 for connecting an external input terminal for transmitting signals (e.g., video signals, clock signals, start signals, reset signals, etc.) and potentials from the outside to the driving circuit section 303 and the driving circuit section 304. Here, an example is shown in which an FPC (flexible printed circuit) 308 is provided as the external input terminal. Note that, although only an FPC is shown here, a printed wiring board (PWB) may be attached to this FPC. In this specification, the light-emitting device includes not only the light-emitting device itself, but also a state in which an FPC or a PWB is attached to it.

Next, the cross-sectional structure will be described with reference to Fig. 3B. A driver circuit portion and a pixel portion are formed on an element substrate 301, and here, a driver circuit portion 303 which is a source line driver circuit, and a pixel portion 302 are shown.

The driving circuit unit 303 is exemplified by a configuration in which a FET 309 and a FET 310 are combined. The driving circuit unit 303 may be formed of a circuit including transistors of a single polarity (either N-type or P-type only), or may be formed of a CMOS circuit including N-type transistors and P-type transistors. In addition, although a driver-integrated type in which a driving circuit is formed on a substrate is shown in this embodiment, this is not necessarily required, and the driving circuit may be formed externally instead of on the substrate.

The pixel section 302 also has a switching FET (not shown) and a current control FET 312. The wiring (source electrode or drain electrode) of the current control FET 312 is connected to the light emitting element 3.
The pixel portion 302 is electrically connected to the first electrodes (anodes) (313a, 313b) of the light-emitting element 317a and the light-emitting element 317b. In this embodiment, the pixel portion 302 is configured using two FETs (a switching FET and a current control FET 312), but the present invention is not limited to this. For example, a configuration in which three or more FETs are combined with a capacitance element may be used.

For example, staggered or inverted staggered transistors can be used as the FETs 309, 310, and 312. For example, group 13 semiconductors, group 14 (silicon, etc.) semiconductors, compound semiconductors, oxide semiconductors, and organic semiconductors can be used as the semiconductor materials for the FETs 309, 310, and 312. The crystallinity of the semiconductor materials is not particularly limited, and for example, an amorphous semiconductor film or a crystalline semiconductor film can be used.
In particular, it is preferable to use an oxide semiconductor for the FETs 309, 310, and 312. Note that, as the oxide semiconductor, for example, In-Ga oxide, In-M-Zn oxide (M is A
FET 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333,
10, 312, for example, an energy gap of 2 eV or more, preferably 2.5 eV
By using an oxide semiconductor material having a voltage of 3 eV or more, more preferably 3 eV or more, the off-state current of a transistor can be reduced.

In addition, the first electrodes (313a, 313b) are provided with conductive films (320a, 320b) for optical adjustment.
For example, when the wavelengths of light extracted by the light-emitting element 317a and the light-emitting element 317b are different from each other as shown in FIG.
The thickness of the first electrodes (313a, 313b) is different from that of the second electrodes (313a, 313b).
Here, the insulator 314 is formed by using a positive type photosensitive acrylic resin.
13b) is used as the anode.

It is also preferable to form a curved surface having a curvature at the upper end or lower end of the insulator 314 .
Forming the shape of the insulator 314 as described above can improve the coverage of a film formed on the insulator 314. For example, either a negative type photosensitive resin or a positive type photosensitive resin can be used as the material of the insulator 314, and not limited to an organic compound, an inorganic compound such as silicon oxide, silicon oxynitride, or silicon nitride can be used.

An EL layer 315 and a second electrode 316 are stacked on the first electrodes (313a and 313b). The EL layer 315 includes at least a light-emitting layer.
313b), an EL layer 315, and a light-emitting element (317a, 317b) including a second electrode 316
In the example shown in FIG. 1B, the end of the EL layer 315 is covered with a second electrode 316.
The structure of the layer 315 may be the same as or different from the single layer structure or stacked layer structure shown in Embodiment 2 or 3. Furthermore, the structure may be different for each light-emitting element.

Note that the materials used for the first electrode 313, the EL layer 315, and the second electrode 316 can be the materials described in Embodiment 2. In addition, the first electrodes (313a, 313b) of the light-emitting elements (317a, 317b) are electrically connected to the lead wiring 307 in the region 321, and an external signal is input through the FPC 308.
, 317b) is electrically connected to a lead wiring 323 in a region 322, and an external signal is input via an FPC 308 (not shown).

In addition, although only two light emitting elements 317 are shown in the cross-sectional view shown in FIG.
02, a plurality of light emitting elements are arranged in a matrix.
The pixel unit 302 includes not only a light emitting element that can emit two types of light (for example, (B, Y)), but also
Light-emitting elements that emit three types of light (e.g., (R, G, B)) or four types of light (e.g., (R, G
A light-emitting device capable of full-color display can be formed by forming light-emitting elements that can emit light of (R, B, Y) or (R, G, B, W), etc., respectively. In addition, the light-emitting layer may be formed by using different materials according to the color of the light emitted by the light-emitting element (so-called color-coded formation), or a plurality of light-emitting elements may have a common light-emitting layer formed of the same material, and may be combined with a color filter to realize full color. In this way, by combining light-emitting elements that can emit several types of light, it is possible to obtain effects such as improved color purity and reduced power consumption. Furthermore, a light-emitting device that improves luminous efficiency and reduces power consumption by combining with quantum dots may be obtained.

Furthermore, a sealing substrate 306 is bonded to the element substrate 301 with a sealing material 305,
The structure is such that light emitting elements 317 a and 317 b are provided in a space 318 surrounded by an element substrate 301 , a sealing substrate 306 , and a sealant 305 .

Further, the sealing substrate 306 is provided with colored layers (color filters) 324, and a black layer (black matrix) 325 is provided between adjacent colored layers. Note that the colored layers (color filters) 324 are provided so as to overlap with the black layer (black matrix) 325.
Light emitted from the light emitting elements 317a and 317b is extracted to the outside via the color layer (color filter) 324.

In addition to the case where the space 318 is filled with an inert gas (nitrogen, argon, or the like), the space 318 may also be filled with the sealant 305. When applying the sealant and bonding the components, it is preferable to perform either a UV treatment or a heat treatment, or a combination of these.

It is preferable to use epoxy resin or glass frit for the sealing material 305. It is also preferable that these materials are as impermeable to moisture and oxygen as possible.
Materials used for the sealing substrate 306 include glass substrates, quartz substrates, and FRP (Fiber-Reinforced Plastics).
In the case where glass frit is used as the sealing material, the element substrate 301 and the sealing substrate 306 may be made of a plastic material such as polyvinyl fluoride (PVF), polyester, or acrylic.
is preferably a glass substrate.

The structure of the FET electrically connected to the light emitting element may be a structure in which the position of the gate electrode is different from that in FIG. 3B, that is, a structure shown in FET 326, FET 327, and FET 328 in FIG. 3C.
3C, the second insulating layer 24 may be provided so as to overlap with the adjacent color layer (color filter) 324 at a position where the second insulating layer 24 overlaps with the black layer (black matrix) 325.

In this way, an active matrix type light emitting device can be obtained.

Further, the light-emitting device which is one embodiment of the present invention can be a passive matrix light-emitting device in addition to the above-described active matrix light-emitting device.

4A and 4B show a passive matrix light emitting device, in which Fig. 4A is a top view of the passive matrix light emitting device and Fig. 4B is a cross-sectional view thereof.

As shown in FIGS. 4A and 4B, a first electrode 402 and an EL layer (40
A light emitting element 405 having a first electrode 402 (403a, 403b, 403c) and a second electrode 404 is formed. The first electrode 402 is island-shaped, and a plurality of first electrodes 402 are formed in a stripe shape in one direction (horizontal direction in FIG. 4A). An insulating film 406 is formed on a part of the first electrode 402. A partition wall 407 made of an insulating material is provided on the insulating film 406. The sidewalls of the partition wall 407 have an inclination such that the distance between one sidewall and the other sidewall becomes narrower as the sidewall approaches the substrate surface, as shown in FIG. 4B.

Since the insulating film 406 has an opening in a part above the first electrode 402, the EL layer (40
4A and 4B, the EL layers (403a, 403b, 403c) and the second electrode 404 can be formed separately in a desired shape on the first electrode 402.
c) and the second electrode 404 are formed.
3B and EL layer 403c each exhibit a different light emission color (for example, red, green, blue, yellow, orange, white, etc.).

In addition, after the EL layers (403a, 403b, and 403c) are formed, the second electrode 404 is formed. Therefore, the second electrode 404 is formed on the EL layers (403a, 403b, and 403c) without being in contact with the first electrode 402.

The sealing method can be performed in the same manner as in the case of an active matrix light emitting device, and therefore the description thereof will be omitted.

In this way, a passive matrix type light emitting device can be obtained.

For example, in this specification and the like, a transistor or a light-emitting element can be formed using various substrates. The type of substrate is not limited to a specific one. Examples of the substrate include a semiconductor substrate (e.g., a single crystal substrate or a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless steel substrate, a substrate having stainless steel foil, a tungsten substrate, a substrate having tungsten foil, a flexible substrate, a laminated film, paper containing a fibrous material, or a base film. Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, or soda lime glass. Examples of flexible substrates, laminated films, base films, and the like include the following. For example, polyethylene terephthalate (PET)
Examples of the material include plastics such as polyethylene terephthalate (PEN), polyethersulfone (PES), and polytetrafluoroethylene (PTFE). Examples of the material include synthetic resins such as acrylic. Examples of the material include polypropylene, polyester, polyvinyl fluoride, and polyvinyl chloride. Examples of the material include
Polyamide, polyimide, aramid, epoxy, inorganic vapor deposition film, paper, etc. In particular, by manufacturing a transistor using a semiconductor substrate, a single crystal substrate, an SOI substrate, etc., there is little variation in characteristics, size, shape, etc., and the current supply capacity is high,
It is possible to manufacture small-sized transistors. When a circuit is constructed using such transistors, it is possible to reduce the power consumption of the circuit or to increase the degree of integration of the circuit.

Alternatively, a flexible substrate may be used as the substrate, and a transistor or a light-emitting element may be formed directly on the flexible substrate. Alternatively, a peeling layer may be provided between the substrate and the transistor or the light-emitting element. The peeling layer can be used to separate the semiconductor device from the substrate after a part or the whole of the semiconductor device is completed thereon, and to transfer the semiconductor device to another substrate. In this case, the transistor or the light-emitting element can be transferred to a substrate having poor heat resistance or a flexible substrate. For example, the above-mentioned peeling layer may be a laminated structure of inorganic films of a tungsten film and a silicon oxide film, or a structure in which an organic resin film such as polyimide is formed on a substrate.

That is, a transistor or a light-emitting element may be formed using a certain substrate, and then the transistor or the light-emitting element may be transferred to another substrate, and the transistor or the light-emitting element may be disposed on the other substrate. Examples of the substrate onto which the transistor or the light-emitting element is transferred include a paper substrate, a cellophane substrate, a quartz ...
Examples of substrates include aramid film substrates, polyimide film substrates, stone substrates, wood substrates, cloth substrates (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester)), leather substrates, and rubber substrates. By using these substrates, it is possible to form transistors with good characteristics, form transistors with low power consumption, manufacture devices that are durable, impart heat resistance, and reduce weight or thickness.

Note that the structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiment modes.

(Embodiment 5)
In this embodiment, examples of various electronic devices and automobiles completed by using a light-emitting device which is one embodiment of the present invention will be described.

Examples of electronic devices to which light-emitting devices are applied include television devices (also called televisions or television receivers), monitors for computers, digital cameras, digital video cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices), portable game machines, personal digital assistants, audio playback devices, large game machines such as pachinko machines, etc. Specific examples of these electronic devices are shown in FIG.

5A shows an example of a television device. In the television device 7100, a display portion 7103 is incorporated in a housing 7101. The display portion 7103 can display an image, and a touch panel (input/output device) equipped with a touch sensor (input device) is also provided.
Note that the light-emitting device which is one embodiment of the present invention can be used for the display portion 7103. Here, the housing 7101 is supported by a stand 7105.

The television device 7100 can be operated using an operation switch provided on the housing 7101 or the
This can be done by a separate remote control 7110 shown in FIG.
The channel and volume can be controlled by using the operation keys 7109 provided on the display unit 7100, and an image displayed on the display unit 7103 can be controlled.
A display portion 7107 for displaying information output from the remote control unit 7110 may be provided.

The television device 7100 is configured to include a receiver, a modem, etc. The receiver can receive general television broadcasts, and by connecting to a wired or wireless communication network via the modem, it is also possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

FIG. 5B shows a computer, which includes a main body 7201, a housing 7202, a display portion 7203, a keyboard 7204, an external connection port 7205, a pointing device 7206, and the like.
Note that the computer can be manufactured by using the light-emitting device which is one embodiment of the present invention for the display portion 7203. The display portion 7203 may be a touch panel (input/output device) equipped with a touch sensor (input device).

FIG. 5C shows a smart watch. The smart watch includes a housing 7302, a display unit 7304, and an operation button 7306.
311, 7312, a connection terminal 7313, a band 7321, a clasp 7322, etc.

A display unit 7304 mounted on a housing 7302 that also serves as a bezel portion has a non-rectangular display area. The display unit 7304 displays an icon 7305 representing the time, other icons 730
6, etc. The display portion 7304 may be a touch panel (input/output device) equipped with a touch sensor (input device).

5C can have various functions. For example, the smartwatch can have a function of displaying various information (still images, videos, text images, etc.) on the display unit, a touch panel function, a function of displaying a calendar, date or time, etc., a function of controlling processing by various software (programs), a wireless communication function, a function of connecting to various computer networks using the wireless communication function, a function of transmitting or receiving various data using the wireless communication function, a function of reading out a program or data recorded on a recording medium and displaying it on the display unit, etc.

The housing 7302 may also have a speaker, a sensor (including a function of measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared ray), a microphone, or the like inside. Note that a smartwatch can be manufactured by using a light-emitting device for the display portion 7304.

FIG. 5D shows an example of a mobile phone (including a smartphone).
The display device 400 includes a housing 7401, a display portion 7402, a microphone 7406, a speaker 7405, a camera 7407, an external connection portion 7404, an operation button 7403, and the like. When a light-emitting device is manufactured by forming a light-emitting element according to one embodiment of the present invention over a flexible substrate,
This can be applied to a display portion 7402 having a curved surface as shown in FIG.

In the mobile phone 7400 shown in FIG. 5D, information can be input by touching the display portion 7402 with a finger or the like.
This can be done by touching the display portion 7402 with a finger or the like.

The screen of the display unit 7402 has three main modes. The first is a display mode mainly for displaying images, the second is an input mode mainly for inputting information such as characters, and the third is a display+input mode in which the display mode and the input mode are combined.

For example, when making a call or composing an e-mail, the display portion 7402 may be set to a character input mode mainly for inputting characters, and the character input operation displayed on the screen may be performed. In this case, it is preferable to display a keyboard or number buttons on most of the screen of the display portion 7402.

In addition, by providing a detection device such as a gyro sensor or an acceleration sensor inside the mobile phone 7400, the orientation of the mobile phone 7400 (portrait or landscape) can be determined and the screen display of the display portion 7402 can be automatically switched.

The screen mode can be switched by touching the display portion 7402 or by operating operation buttons 7403 on the housing 7401. The screen mode can also be switched depending on the type of image displayed on the display portion 7402. For example, if the image signal to be displayed on the display portion is moving image data, the display mode is selected, and if the image signal is text data, the input mode is selected.

In addition, in the input mode, a signal detected by an optical sensor in the display portion 7402 may be detected, and if there is no input by touch operation on the display portion 7402 for a certain period of time, the screen mode may be controlled to be switched from the input mode to the display mode.

The display portion 7402 can also function as an image sensor.
By touching the display 02 with a palm or finger and capturing an image of a palm print, fingerprint, etc., personal authentication can be performed. In addition, by using a backlight that emits near-infrared light or a sensing light source that emits near-infrared light in the display unit, it is possible to capture an image of finger veins, palm veins, etc.

Furthermore, as another configuration of a mobile phone (including a smartphone), the present invention can be applied to a mobile phone having a structure as shown in FIG. 5 (D'-1) or FIG. 5 (D'-2).

In addition, in the case of a structure such as that shown in FIG. 5(D'-1) or FIG. 5(D'-2), character information, image information, etc. are stored on the first surfaces 7501(1) and 7501(2) of the housings 7500(1) and 7500(2).
(2), but also on the second surfaces 7502(1) and 7502(2).
With this structure, the mobile phone can be stored in a breast pocket without
The user can easily check the text information, image information, etc. displayed on the second surfaces 7502(1), 7502(2), etc.

In addition, as an electronic device to which a light-emitting device is applied, a foldable portable information terminal as shown in FIGS. 6A to 6C can be given. FIG. 6A shows a portable information terminal 931 in an unfolded state.
6B shows the portable information terminal 9310 in a state in which it is changing from one of the unfolded state and the folded state to the other. Furthermore, Fig. 6C shows the portable information terminal 9310 in a folded state. The portable information terminal 9310 has excellent portability in the folded state, and has excellent display viewability due to a seamless wide display area in the unfolded state.

The display portion 9311 is supported by three housings 9315 connected by hinges 9313. Note that the display portion 9311 may be a touch panel (input/output device) equipped with a touch sensor (input device). In addition, the display portion 9311 can reversibly change the state of the portable information terminal 9310 from an unfolded state to a folded state by bending the two housings 9315 via the hinges 9313.
The display portion 9311 can be used as the portable information terminal 9310. A display area 9312 in the display portion 9311 is a display area located on a side of the portable information terminal 9310 in a folded state. The display area 9312 can display information icons, frequently used applications, shortcuts to programs, and the like, so that information can be checked and applications can be started smoothly.

7A and 7B show automobiles to which the light-emitting device is applied. That is, the light-emitting device can be provided integrally with the automobile. Specifically, the light-emitting device can be applied to the exterior light 5101 (including the rear of the vehicle body), the wheel 5102 of the tire, and a part or the whole of the door 5103 of the automobile shown in FIG. 7A. Also, the display unit 51 inside the automobile shown in FIG.
04, a steering wheel 5105, a shift lever 5106, a seat 5107, an inner rear view mirror 5108, etc. In addition, it may be applied to a part of a glass window.

In the above manner, an electronic device or an automobile can be obtained by applying the light-emitting device according to one embodiment of the present invention. Note that the electronic devices and automobiles to which the present invention can be applied are not limited to those described in this embodiment, and the present invention can be applied in any field.

Note that the structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiment modes.

(Embodiment 6)
In this embodiment, a structure of a lighting device manufactured using a light-emitting element which is one embodiment of the present invention will be described with reference to FIGS.

8A, 8B, 8C, and 8D are cross-sectional views of an example of a lighting device.
(A) and (B) are bottom emission type lighting devices that extract light to the substrate side, as shown in FIG.
3C) and 3D are top emission type lighting devices that extract light on the sealing substrate side.

8A includes a light-emitting element 4002 over a substrate 4001. A substrate 4003 having projections and recesses on the outer side of the substrate 4001 is also included. The light-emitting element 4002 includes a first electrode 4004, an EL layer 4005, and a second electrode 4006.

The first electrode 4004 is electrically connected to the electrode 4007, and the second electrode 4006 is electrically connected to the electrode 4008.
4008. An auxiliary wiring 4009 may be provided which is electrically connected to the first electrode 4004. Note that an insulating layer 4010 is formed over the auxiliary wiring 4009.

The substrate 4001 and the sealing substrate 4011 are bonded to each other with a sealant 4012.
It is preferable that a desiccant 4013 is provided between the sealing substrate 4011 and the light emitting element 4002. Note that since the substrate 4003 has projections and recesses as shown in FIG.
The efficiency of extracting the light generated in .02 can be improved.

In addition, instead of the substrate 4003, a diffusion plate 4015 may be provided on the outer side of the substrate 4001 as in a lighting device 4100 of FIG.

8C includes a light-emitting element 4202 over a substrate 4201. The light-emitting element 4202 includes a first electrode 4204, an EL layer 4205, and a second electrode 4206.

The first electrode 4204 is electrically connected to the electrode 4207, and the second electrode 4206 is electrically connected to the electrode 4208.
208 is electrically connected to the second electrode 4206.
An insulating layer 4210 may be provided under the auxiliary wiring 4209.

The substrate 4201 and the sealing substrate 4211 having projections and recesses are bonded with a sealant 4212. In addition, a barrier film 4213 and a planarization film 421 are provided between the sealing substrate 4211 and the light emitting element 4202.
Since the sealing substrate 4211 has projections and recesses as shown in FIG.
The extraction efficiency of light generated by the light emitting element 4202 can be improved.

In addition, instead of the sealing substrate 4211, a light-emitting element 4
A diffusion plate 4215 may be provided on top of 202 .

Note that the lighting device described in this embodiment may have a structure including a light-emitting element which is one embodiment of the present invention, and a housing, a cover, or a support base.
An organometallic complex which is one embodiment of the present invention can be applied to 4205. In this case, a lighting device with low power consumption can be provided.

Note that the structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiment modes.

(Seventh embodiment)
In this embodiment, an example of a lighting device, which is an application of the light-emitting device according to one embodiment of the present invention, will be described with reference to FIGS.

9 shows an example in which the light-emitting device is used as an indoor lighting device 8001. Since the light-emitting device can be enlarged, a large-area lighting device can also be formed. In addition, by using a housing having a curved surface, a lighting device 8002 in which the light-emitting region has a curved surface can also be formed. The light-emitting element included in the light-emitting device shown in this embodiment mode is a thin film, and the housing can be designed with a high degree of freedom. Therefore, lighting devices with various elaborate designs can be formed.
Furthermore, lighting devices 8003 may be provided on the walls inside the room.

In addition to the above, by applying the light emitting device to a part of furniture provided in a room, a lighting device having a function as furniture can be provided.

As described above, various lighting devices using the light-emitting device can be obtained. Note that these lighting devices are included in one embodiment of the present invention.

The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiment modes.

(Embodiment 8)
In this embodiment, a touch panel including a light-emitting element of one embodiment of the present invention or a light-emitting device of one embodiment of the present invention will be described with reference to FIGS.

10(A) and (B) are perspective views of the touch panel 2000.
) representative components of touch panel 2000 are shown for clarity.

The touch panel 2000 includes a display panel 2501 and a touch sensor 2595 (see FIG. 1).
0(B)). The touch panel 2000 also includes a substrate 2510, a substrate 2570, and a substrate 2590.

The display panel 2501 has a plurality of pixels over a substrate 2510 and a plurality of wirings 2511 capable of supplying signals to the pixels. The plurality of wirings 2511 are routed to the outer periphery of the substrate 2510, and a part of the wirings 2511 constitutes a terminal 2519. The terminal 2519 is connected to an FPC 2509.
(1) and electrically connected.

The substrate 2590 includes a touch sensor 2595 and a plurality of wirings 2598 electrically connected to the touch sensor 2595. The plurality of wirings 2598 are routed around the outer periphery of the substrate 2590, and some of them form terminals 2599. The terminals 2599 are connected to an FPC 2509 (
10B, for clarity, electrodes, wirings, and the like of the touch sensor 2595 provided on the back surface side of the substrate 2590 (the surface facing the substrate 2510) are shown by solid lines.

For example, a capacitive touch sensor can be used as the touch sensor 2595. The capacitive touch sensor includes a surface capacitive touch sensor, a projected capacitive touch sensor, and the like.

The projected capacitive type is classified into a self-capacitance type, a mutual capacitance type, etc., mainly depending on the driving method. The mutual capacitance type is preferable because it enables simultaneous multi-point detection.

First, a case where a projected capacitive touch sensor is applied will be described with reference to Fig. 10B. In the case of the projected capacitive touch sensor, various sensors capable of detecting the proximity or contact of a detection target such as a finger can be applied.

The projected capacitive touch sensor 2595 has an electrode 2591 and an electrode 2592. The electrode 2591 and the electrode 2592 are electrically connected to different wirings among a plurality of wirings 2598. As shown in Figures 10 (A) and (B) , the electrode 2592 has a shape in which a plurality of quadrilaterals repeatedly arranged in one direction are connected in one direction at their corners by wirings 2594. The electrode 2591 also has a shape in which a plurality of quadrilaterals are connected in one direction at their corners, but the connection direction intersects with the direction in which the electrode 2592 is connected. Note that the electrode 2591
The direction in which the electrode 2592 is connected does not necessarily have to be perpendicular to the direction in which the electrode 2592 is connected, and they may be arranged to form an angle greater than 0 degrees and less than 90 degrees.

Note that it is preferable that the area of the intersection of the wiring 2594 with the electrode 2592 be as small as possible. This can reduce the area of a region where no electrode is provided, and can reduce variations in transmittance. As a result, variations in luminance of light passing through the touch sensor 2595 can be reduced.

Note that the shapes of the electrodes 2591 and 2592 are not limited to this and may take various shapes. For example, a configuration may be used in which a plurality of electrodes 2591 are arranged so that there is as little gap as possible, and a plurality of electrodes 2592 are provided with an insulating layer interposed therebetween. In this case, the two adjacent electrodes 2592 may be arranged so that the electrodes 2591 are arranged so that there is as little gap as possible between the electrodes 2591 and the electrodes 2592.
It is preferable to provide a dummy electrode between the first and second electrodes, which is electrically insulated from the first and second electrodes, since this can reduce the area of the region with different transmittances.

Next, the touch panel 2000 will be described in detail with reference to FIG.
1 corresponds to a cross-sectional view taken along dashed line X1-X2 in FIG.

The touch panel 2000 has a touch sensor 2595 and a display panel 2501.

The touch sensor 2595 includes electrodes 2591 and electrodes 2592 arranged in a staggered pattern in contact with a substrate 2590, an insulating layer 2593 covering the electrodes 2591 and the electrodes 2592, and wiring 2594 electrically connecting adjacent electrodes 2591. Note that an electrode 2592 is provided between adjacent electrodes 2591.

The electrode 2591 and the electrode 2592 can be formed using a conductive material having a light-transmitting property. As the conductive material having a light-transmitting property, a conductive oxide such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, or zinc oxide to which gallium is added can be used. A graphene compound can also be used. Note that when a graphene compound is used, the electrode 2591 and the electrode 2592 can be formed by reducing, for example, graphene oxide formed in a film shape. Examples of a reduction method include a method of applying heat and a method of irradiating a laser.

The electrode 2591 and the electrode 2592 can be formed, for example, by forming a light-transmitting conductive material on the substrate 2590 by a sputtering method, and then removing unnecessary portions by various patterning techniques such as photolithography.

Examples of materials that can be used for the insulating layer 2593 include resins such as acrylic and epoxy, resins having siloxane bonds, and inorganic insulating materials such as silicon oxide, silicon oxynitride, and aluminum oxide.

In addition, the adjacent electrodes 2591 are electrically connected to each other through a wiring 2594 formed in a part of the insulating layer 2593.
It is preferable to use a material having a higher electrical conductivity than the material used for the second electrode 2 since the electrical resistance can be reduced by using such a material.

In addition, the wiring 2598 is electrically connected to the electrode 2591 or the electrode 2592.
A part of the wiring 2598 functions as a terminal. For the wiring 2598, for example, a metal material such as aluminum, gold, platinum, silver, nickel, titanium, tungsten, chromium, molybdenum, iron, cobalt, copper, or palladium, or an alloy material containing such a metal material can be used.

The wiring 2598 and the FPC 2509(2) are electrically connected to the terminal 2599. The terminal 2599 may be made of any of various anisotropic conductive films (ACF: Anisotropic Conductive Films).
Conductive Film) and Anisotropic Conductive Paste (ACP)
For example, a cyclodextrin (tropic conductive paste) can be used.

In addition, an adhesive layer 2597 is provided in contact with the wiring 2594.
95 is attached to the display panel 2501 so as to overlap with it via an adhesive layer 2597 .
Note that the surface of the display panel 2501 in contact with the adhesive layer 2597 may have a substrate 2570 as shown in FIG. 11A, but this is not necessarily required.

The adhesive layer 2597 has light-transmitting properties. For example, a thermosetting resin or an ultraviolet curing resin can be used, and specifically, an acrylic resin, a urethane resin, an epoxy resin, or a siloxane resin can be used.

11A includes a plurality of pixels and a driver circuit arranged in a matrix between a substrate 2510 and a substrate 2570. Each pixel includes a light-emitting element and a pixel circuit for driving the light-emitting element.

FIG. 11A shows a pixel 2502R as an example of a pixel of a display panel 2501, and a scanning line driver circuit 2503g as an example of a driver circuit.

The pixel 2502R includes a light-emitting element 2550R and a transistor 2502t capable of supplying power to the light-emitting element 2550R.

The transistor 2502t is covered with an insulating layer 2521. Note that the insulating layer 2521 is
It has a function of flattening unevenness caused by previously formed transistors, etc.
A function of suppressing diffusion of impurities may be imparted to the insulating layer 2521. In this case, a decrease in reliability of a transistor or the like due to diffusion of impurities can be suppressed, which is preferable.

The light-emitting element 2550R is electrically connected to the transistor 2502t through a wiring. Note that one electrode of the light-emitting element 2550R is directly connected to the wiring. Note that an end of the one electrode of the light-emitting element 2550R is covered with an insulator 2528.

The light-emitting element 2550R has an EL layer between a pair of electrodes.
A coloring layer 2567R is provided at a position overlapping the light emitting element 2550R, and a part of the light emitted by the light emitting element 2550R is transmitted through the coloring layer 2567R and is emitted in the direction of the arrow shown in the figure. In addition, a light shielding layer 2567BM is provided at the end of the coloring layer, and the light emitting element 2550R and the coloring layer 2567R
A sealing layer 2560 is provided between them.

When the sealing layer 2560 is provided in a direction in which light from the light emitting element 2550R is extracted, it is preferable that the sealing layer 2560 has light-transmitting properties. It is also preferable that the sealing layer 2560 has a refractive index higher than that of air.

The scanning line driver circuit 2503g includes a transistor 2503t and a capacitor 2503c. Note that the driver circuit can be formed over the same substrate as the pixel circuit in the same process.
) is also covered with an insulating layer 2521.

A wiring 2511 capable of supplying a signal to the transistor 2503t is provided. A terminal 2519 is provided in contact with the wiring 2511.
It is electrically connected to the FPC 2509(1), which has a function of supplying signals such as image signals and synchronization signals. A printed wiring board (PWB) may be attached to the FPC 2509(1).

Although a bottom-gate transistor is used in the display panel 2501 shown in FIG. 11A, the structure of the transistor is not limited to this, and transistors having various structures can be used.
A semiconductor layer containing an oxide semiconductor can be used as a channel region of the transistor 502t and the transistor 2503t. Alternatively, a semiconductor layer containing amorphous silicon or a semiconductor layer containing polycrystalline silicon crystallized by treatment such as laser annealing can be used as a channel region of the transistor 2503t.

11B shows a structure in the case where a top-gate transistor different from the bottom-gate transistor shown in FIG 11A is applied to the display panel 2501. Note that even if the structure of the transistor is changed, the same variations that can be used for the channel region are applicable.

The touch panel 2000 shown in Fig. 11A preferably has an anti-reflection layer 2567p at least overlapping with the pixels on the surface from which light from the pixels is emitted to the outside as shown in Fig. 11A. Note that a circularly polarizing plate or the like can be used as the anti-reflection layer 2567p.

The substrate 2510, the substrate 2570, and the substrate 2590 shown in FIG. 11A may have a water vapor permeability of, for example, 1×10 ⁻⁵ g/(m ² ·day) or less, preferably 1×10 ⁻⁶ g/(m 2 ·day) or less.
It is preferable to use a material having flexibility with a thermal expansion coefficient of 1×10 ^{−3 /} K or less, preferably 5×10 ⁻⁵ /K or less, and more preferably 1×10 ^−
5 /K or less.

Next, a touch panel 2000' having a different configuration from the touch panel 2000 shown in Fig. 11 will be described with reference to Fig. 12. However, the touch panel 2000' can be applied as a touch panel in the same manner as the touch panel 2000.

FIG. 12 shows a cross-sectional view of a touch panel 2000′. The touch panel 200 shown in FIG.
11 in that the position of the touch sensor 2595 with respect to the display panel 2501 is different. Only the different configurations will be described here, and the description of the touch panel 2000 will be cited for parts where a similar configuration can be used.

The coloring layer 2567R is located so as to overlap with the light emitting element 2550R. Light from the light emitting element 2550R shown in FIG. 12A is emitted in the direction in which the transistor 2502t is provided. That is, (a part of) the light from the light emitting element 2550R is transmitted through the coloring layer 2567R and emitted in the direction of the arrow shown in the figure. Note that the light shielding layer 2567R is provided at the end of the coloring layer 2567R.
67BM is provided.

The touch sensor 2595 is provided on the side of the display panel 2501 on which the transistor 2502t is provided as viewed from the light-emitting element 2550R (see FIG. 12A).

The adhesive layer 2597 is in contact with a substrate 2510 of the display panel 2501.
In the case of the structure shown in FIG. 2(A), a display panel 2501 and a touch sensor 2595 are attached to each other. However, a structure in which the substrate 2510 is not provided between the display panel 2501 and the touch sensor 2595 that are attached to each other by an adhesive layer 2597 may be used.

As in the case of the touch panel 2000, transistors having various structures can be applied to the display panel 2501 in the case of the touch panel 2000′.
In the above, a case where a bottom-gate transistor is applied is shown.
As shown in FIG. 2B, a top-gate transistor may be used.

Next, an example of a method for driving a touch panel will be explained using Figure 13.

FIG. 13A is a block diagram showing the configuration of a mutual capacitance type touch sensor.
13A shows a pulse voltage output circuit 2601 and a current detection circuit 2602. Note that in FIG. 13A, an electrode 2621 to which a pulse voltage is applied is designated as X1-X6, and an electrode 2622 to detect a change in current is designated as Y1-Y6, and six wirings are used for each. Also, in FIG. 13A, a capacitance 2 formed by overlapping the electrode 2621 and the electrode 2622 is shown.
603. Note that the functions of the electrode 2621 and the electrode 2622 may be interchangeable.

The pulse voltage output circuit 2601 is a circuit for applying a pulse voltage to the wirings X1-X6 in sequence. By applying a pulse voltage to the wirings X1-X6, an electric field is generated between the electrodes 2621 and 2622 that form the capacitance 2603. The electric field generated between the electrodes changes the mutual capacitance of the capacitance 2603 due to shielding or the like, and this can be utilized to detect the proximity or contact of a detection target.

The current detection circuit 2602 is a circuit for detecting a change in current in the wirings Y1 to Y6 due to a change in mutual capacitance in the capacitor 2603. In the wirings Y1 to Y6, there is no change in the detected current value if there is no proximity or contact with a sensed object, but when the mutual capacitance decreases due to the proximity or contact of a sensed object to be detected, a change in the current value that decreases is detected. Note that the detection of the current may be performed using an integrating circuit or the like.

Next, FIG. 13B shows a timing chart of input/output waveforms in the mutual capacitance touch sensor shown in FIG. 13A. In FIG. 13B, detection of an object to be detected in each row and column is performed in one frame period. FIG. 13B also shows two cases: when an object to be detected is not detected (non-touched) and when an object to be detected is detected (touched). Note that for the wiring Y1-Y6, waveforms are shown with voltage values corresponding to the detected current values.

A pulse voltage is applied to the wires X1-X6 in sequence, and the wires Y1-Y
When the sensed object is not approaching or touching, the waveform of the Y1-Y6 wires changes in accordance with the change in voltage of the X1-X6 wires. On the other hand, when the sensed object is approaching or touching, the current value decreases, and the waveform of the corresponding voltage value also changes. In this way, the proximity or contact of the sensed object can be detected by detecting the change in mutual capacitance.

13A shows a configuration of a passive touch sensor in which only a capacitor 2603 is provided at an intersection of wirings as a touch sensor, but an active touch sensor including a transistor and a capacitor may be used. FIG 14 shows an example of one sensor circuit included in an active touch sensor.

The sensor circuit shown in FIG. 14 includes a capacitor 2603, a transistor 2611, and a transistor 2620.
612 and a transistor 2613.

A signal G2 is applied to the gate of the transistor 2613, a voltage VRES is applied to one of the source and drain of the transistor 2613, and the other is electrically connected to one electrode of the capacitor 2603 and the gate of the transistor 2611. One of the source and drain of the transistor 2611 is electrically connected to one of the source and drain of the transistor 2612, and the other is connected to a voltage VSS.
A signal G1 is applied to the gate of the transistor 2612, and the other of the source and the drain is electrically connected to the wiring ML.
is given.

14 will be described. First, a potential that turns on the transistor 2613 is applied as the signal G2, and a potential corresponding to the voltage VRES is applied to the node n to which the gate of the transistor 2611 is connected. Next, a potential that turns off the transistor 2613 is applied as the signal G2, and the potential of the node n is held. Next, the mutual capacitance of the capacitance 2603 changes due to the approach or contact of a detected object such as a finger, and the potential of the node n changes from VRES.

In the read operation, a potential that turns on the transistor 2612 is applied as the signal G1.
The current flowing through the transistor 2611, that is, the current flowing through the wiring ML, changes depending on the potential of the node n. By detecting this current, the proximity or contact of an object to be detected can be detected.

An oxide semiconductor layer is preferably used as a semiconductor layer in which a channel region is formed for each of the transistors 2611, 2612, and 2613. In particular, by using such a transistor as the transistor 2613, the potential of the node n can be held for a long period of time, and the frequency of an operation of resupplying VRES to the node n (refresh operation) can be reduced.

This embodiment mode can be implemented by appropriately combining at least a part of it with other embodiment modes described in this specification.

Synthesis Example 1
In this example, a heterocyclic compound, 2-[3-(benzo[1,2-b:
A method for synthesizing 4,5-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbfPDBq) (structural formula (101)) will be described. The structure of 2mBbfPDBq is shown below.

<Synthesis of 2mBbfPDBq>
<Step 1>
In a 200 mL three-neck flask, 8.9 g (30 mmol) of 1,4-dibromo-2,5-
Dimethoxybenzene, 10 g (72 mmol) of 2-fluorophenylboronic acid, and 1
5 mL of toluene and 15 mL of diethylene glycol dimethyl ether (diglym
e) and 60 mL of an aqueous sodium carbonate solution (2.0 mol/L) were added, and the mixture was degassed by stirring while reducing the pressure inside the flask.

After degassing, the system was purged with a nitrogen gas flow, and the mixture was heated to 80° C.
69 g (0.60 mmol) of tetrakis(triphenylphosphine)palladium (0
) was added and stirred at the same temperature for 2 hours. The mixture was cooled to room temperature and then degassed again under reduced pressure. The system was placed under a nitrogen stream and then heated to 80° C. After heating, 0.69 g (0.60 mm
ol) tetrakis(triphenylphosphine)palladium(0) was added, and the mixture was heated at the same temperature for 5 hours.

After heating, 2.0 g (14 mmol) of 2-fluorophenylboronic acid was added, and the mixture was stirred at the same temperature for an additional 3 hours. After heating, the mixture was allowed to cool to room temperature, degassed under reduced pressure, and the system was placed under a nitrogen stream. This mixture was heated to 80°C, and 0.64 g (0.55 mmol) of tetrakis(triphenylphosphine)palladium(0) and 3.0 g (21 mmol) of 2-fluorophenylboronic acid were added, and the mixture was stirred at the same temperature for 2 hours. After stirring, the mixture was allowed to cool to room temperature,
The organic and aqueous layers were separated.

The obtained aqueous layer was extracted three times with toluene, and the extract and the organic layer were combined, washed with saturated saline, and dried with anhydrous magnesium sulfate. The obtained mixture was naturally filtered, and the filtrate was concentrated to obtain a compound. The obtained compound was recrystallized with toluene to obtain 2.5 g of the target product. The compound obtained by concentrating the filtrate was purified by column chromatography (developing solvent: hexane:ethyl acetate=30:1), and 0.3 g of the target product was obtained.
A total of 2.8 g of the target product was obtained in a yield of 29%. A synthesis scheme showing the above synthesis method is shown in the following formula (A-1).

<Step 2>
In a 300 mL three-neck flask, 2.8 g (8.7 mmol) of 1,4-bis(2-fluorophenyl)-2,5-dimethoxybenzene was placed, and the flask was purged with nitrogen gas. Then, 20 mL of dehydrated dichloromethane was added to obtain a solution. This solution was placed in an ice bath and stirred, and 21 mL (21 mmol) of boron tribromide solution (1 mol/L dichloromethane solution) was added to this solution.
A solution prepared by diluting 100 mL of the above-mentioned mixture with 22 mL of dehydrated dichloromethane was added dropwise, and after the addition, the resulting solution was stirred at room temperature for about 15 hours.

After stirring, the resulting solution was cooled in an ice bath, and 10 mL of water and 5 mL of methanol were added dropwise. After the addition, the precipitated solid was collected by suction filtration to obtain a white solid as the target substance. The resulting filtrate was separated into an organic layer and an aqueous layer, and the resulting aqueous layer was extracted three times with dichloromethane. The extract and the organic layer were combined, washed with an aqueous sodium bicarbonate solution and saturated saline, and dried with anhydrous magnesium sulfate. The mixture was naturally filtered, and the filtrate was concentrated to obtain a white solid as the target substance. A synthesis scheme showing the above synthesis method is shown in the following formula (A-
2).

<Step 3>
In a 100 mL three-neck flask, add 2.3 g (7.8 mmol) of the 1,4-
Bis(2-fluorophenyl)-2,5-dihydroxybenzene, 4.2 g (30 mm
100 ml of potassium carbonate and 44 mL of N-methyl-2-pyrrolidinone were added, and the mixture was degassed by stirring while reducing the pressure inside the flask. After degassing, the system was purged with a nitrogen gas stream, and then
This mixture was stirred for 4.5 hours at 200° C. After stirring, it was allowed to cool to room temperature, and then toluene, water and hydrochloric acid were added and stirred to separate the organic layer and the aqueous layer.

The aqueous layer obtained was extracted three times with toluene. When the obtained extract and the organic layer were combined, a solid precipitated, and the precipitated solid was collected by suction filtration. The obtained filtrate was washed with an aqueous sodium hydrogen carbonate solution and saturated saline, and dried with anhydrous magnesium sulfate. This mixture was naturally filtered, and the filtrate was concentrated to obtain a solid. The solid thus obtained was recrystallized with toluene to obtain 0.53 g of the target solid. The previously precipitated solid was recrystallized with toluene to obtain 0.94 g of the target white solid. The total amount of the target solid was 1.5 g (5.7 mmol).
The synthesis method was carried out in a yield of 73%.

<Step 4>
In a 100 mL three-neck flask, 1.4 g (5.5 mmol) of benzo[1,2-b:4,
After placing 5-b']bisbenzofuran in the flask and placing the flask under a nitrogen stream, 34 mL of dehydrated tetrahydrofuran was added, and the resulting solution was stirred at -78°C.
L of n-butyllithium hexane solution (1.6 mol/L, 6.3 mmol) was added dropwise,
After the dropwise addition, the mixture was stirred at the same temperature for 20 minutes, then warmed to room temperature and stirred for 1 hour. After a predetermined time had elapsed, the resulting solution was cooled to -78°C, and after cooling, 1.5 mL (13 mmol) of trimethyl borate was added dropwise at the same temperature.

The resulting solution was warmed to room temperature and stirred at room temperature for 15 hours. After stirring, 50 mL of hydrochloric acid (1
mol/L) was added and the mixture was stirred for 1 hour. After stirring, the organic layer and the aqueous layer were separated, and the obtained aqueous layer was extracted twice with ethyl acetate. The obtained extract and the organic layer were combined and
The mixture was washed with an aqueous solution of sodium hydrogen carbonate and saturated saline, and dried with anhydrous magnesium sulfate. The mixture was gravity filtered, and the filtrate was concentrated to obtain a solid.

The solid obtained was washed with chloroform and filtered by suction to obtain 0.53 g of the target solid. The filtrate obtained was concentrated to obtain a compound, which was recrystallized from toluene/hexane.
The total amount of the target solid was 1.1 g (3.7 mmol).
The synthesis method was carried out in a yield of 67%. The synthesis scheme showing the above synthesis method is shown in the following formula (A-4).

<Step 5>
In a 100 mL three-neck flask, 1.2 g (3.1 mmol) of 2-(3-bromophenyl)dibenzo[f,h]quinoxaline and 1.1 g (3.6 mmol) of benzo[1,2-
b: 4,5-b']bisbenzofuran-6-boronic acid, 50 mg (0.16 mmol)
tris(2-methylphenyl)phosphine, 15 mL of toluene, 2 mL of ethanol, and 5 mL of an aqueous potassium carbonate solution (2.0 mol/L) were added to the flask, and the mixture was degassed by stirring while reducing the pressure inside the flask.

After degassing, the flask was conditioned under a nitrogen gas flow, and the mixture was heated to 80° C. To this mixture, 10 mg (45 μmol) of palladium (II) acetate was added, and the mixture was stirred for 7 hours. After stirring, the mixture was allowed to cool to room temperature, and the precipitated solid was collected by suction filtration. The obtained solid was washed with water and ethanol to obtain the target solid. The obtained solid was dissolved in toluene by heating, and the obtained solution was filtered through Celite and alumina. The obtained filtrate was concentrated to obtain a solid, which was recrystallized with toluene to obtain 1.0 g (1.8 mmol) of the target solid.
), with a yield of 58%.

The obtained 1.0 g of solid was purified by train sublimation. The purification was performed by heating the solid at 335° C. for 16.5 hours under a pressure of 2.6 Pa while flowing argon at a flow rate of 5 mL/min. After the purification by sublimation, 0.61 g of the target pale yellow solid was obtained, with a recovery rate of 5.
The synthesis method was obtained at a yield of 9%. The synthesis scheme showing the above synthesis method is shown in the following formula (A-5).

The results of analysis of the pale yellow solid obtained by the above synthesis method by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) are shown below. The ¹ H-NMR chart is shown in Figure 15. From these results, it was found that in Synthesis Example 1, the heterocyclic compound 2mBbfPDBq, which is one embodiment of the present invention and is represented by the above structural formula (101), was obtained.

¹ H NMR (tetrachloroethane-d ₂ , 500 MHz): δ=7.25 (t, J=7
． 5Hz, 1H), 7.48(t, J=7.5Hz, 1H), 7.52-7.59(m,
2H), 7.67 (d, J = 8.0 Hz, 1H), 7.72 (d, J = 8.0 Hz, 1H
), 7.77 (t, J = 7.0 Hz, 2H), 7.82-7.89 (m, 3H), 7.9
8 (t, J = 7.5 Hz, 1H), 8.09 (d, J = 7.5 Hz, 1H), 8.16 (
d, J = 7.5 Hz, 1H), 8.22 (d, J = 1.0 Hz, 1H), 8.63 (d,
J = 7.5 Hz, 1H), 8.71 (d, J = 7.5 Hz, 2H), 8.88 (s, 1H
), 9.34 (d, J = 8.0 Hz, 1H), 9.43 (d, J = 8.0 Hz, 1H),
9.57 (s, 1H).

Next, the ultraviolet-visible absorption spectrum (hereinafter, simply referred to as "absorption spectrum") and emission spectrum of the toluene solution and solid thin film of 2mBbfPDBq were measured. The solid thin film was prepared on a quartz substrate by vacuum deposition. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (V550 model, manufactured by JASCO Corporation). The emission spectrum was measured using a fluorometer (
The absorption spectrum and emission spectrum of the obtained toluene solution are shown in FIG. 16(A). The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity. The absorption spectrum and emission spectrum of the solid thin film are shown in FIG. 16(B).
The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity.

From the results of FIG. 16(A), in the toluene solution of 2 mBbfPDBq, the peaks at 282 nm and 3
An absorption peak was observed at about 33 nm, and emission wavelength peaks were observed at about 392 nm and 404 nm.
Absorption peaks were observed near 63 nm and 337 nm, and an emission wavelength peak was observed near 429 nm.

Synthesis Example 2
In this example, a heterocyclic compound, 2-[3-(benzo[1,2-b:
A method for synthesizing [5,4-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(II)PDBq) (structural formula (107)) will be described. The structure of 2mBbf(II)PDBq is shown below.

<Synthesis of 2mBbf(II)PDBq>
<Step 1>
5.0 g (36 mmol) of 1,3-dimethoxybenzene was placed in a 200 mL three-neck flask, and the flask was depressurized while stirring and degassing. After degassing, the system was placed under a nitrogen stream, and 80 mL of dehydrated dichloromethane was added and stirred. While the resulting solution was cooled in an ice bath, a solution of 12 g (75 mmol) of bromine dissolved in 14 mL of dehydrated dichloromethane was added dropwise to the flask.

After the dropwise addition, the resulting solution was stirred at room temperature for 15 hours. After stirring, while the resulting solution was cooled in an ice bath, an aqueous solution of sodium bicarbonate and an aqueous solution of saturated sodium thiosulfate were added until the pH reached 8. The resulting mixture was separated into an organic layer and an aqueous layer, and the aqueous layer was diluted with dichloromethane for 3 h.
The extract and the organic layer were combined and washed with saturated saline. The organic layer was dried over anhydrous magnesium sulfate, and the mixture was gravity filtered to obtain a filtrate.

The filtrate was concentrated to obtain a solid, to which hexane was added and ultrasonically irradiated, and the mixture was then suction filtered to obtain a solid. The solid was recrystallized from hexane/ethyl acetate to obtain 7.2 g (24 mmol) of the target solid in a yield of 67%. The synthesis scheme showing the above synthesis method is shown in the following formula (B-1).

<Step 2>
Into a 200 mL three-neck flask, 7.1 g (24 mmol) of 1,5-dibromo-2,4-
dimethoxybenzene, 2.8 g (20 mmol) of 2-fluorophenylboronic acid,
12 mL of toluene, 12 mL of diethylene glycol dimethyl ether, and 50 mL
The mixture was degassed by stirring while reducing the pressure inside the flask. After degassing, the system was conditioned under a nitrogen gas flow, and the mixture was heated to 80°C.

To this mixture, 0.55 g (0.48 mmol) of tetrakis(triphenylphosphine)palladium(0) was added and stirred at the same temperature for 3 hours.
(32 mmol) of 2-fluorophenylboronic acid and 0.12 g (0.29 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl were added, and the mixture was degassed under reduced pressure, and the inside of the system was again placed under a nitrogen stream and heated to 80°C.
3 mmol) of palladium(II) acetate was added, and the mixture was stirred at the same temperature for 4 hours.

After stirring, the mixture was allowed to cool to room temperature and separated into an organic layer and an aqueous layer. The resulting aqueous layer was extracted three times with toluene, and the extract and the organic layer were combined, washed with saturated saline, and dried with anhydrous magnesium sulfate. The resulting mixture was gravity filtered, and the filtrate was concentrated to obtain a brown oily product. This oily product was purified by silica gel column chromatography (the developing solvent was a gradient from hexane to chloroform), and the target pale yellow oily product was obtained in 7.
The synthesis method was carried out in a yield of 92%. The synthesis scheme showing the above synthesis method is shown in the following formula (B-2).

<Step 3>
Into a 500 mL three-neck flask, 7.2 g (22 mmol) of 1,5-bis(2-fluorophenyl)-2,4-dimethoxybenzene was placed, and the flask was purged with a nitrogen gas stream.
60 mL of dehydrated dichloromethane was added to obtain a solution. The obtained solution was placed in an ice bath and stirred.
To this solution, 53 mL (53 mm) of boron tribromide solution (1 mol/L dichloromethane solution) was added.
A solution of 100 ml of 1.5 mol of 100 ml of dichloromethane was added dropwise, and the resulting solution was stirred at room temperature for 15 hours. After stirring, the solution was cooled in an ice bath again, and 40 ml of methanol and 4
0 mL of water was added dropwise, and the organic layer and the aqueous layer of the obtained mixture were separated. The obtained aqueous layer was extracted three times with dichloromethane, and the obtained extract and the organic layer were combined and washed with an aqueous sodium hydrogen carbonate solution and saturated saline, and then dried with anhydrous magnesium sulfate. The obtained mixture was naturally filtered, and the filtrate was concentrated, to obtain about 7 g of a pale yellow oily product as the target product. The synthesis scheme showing the above synthesis method is shown in the following formula (B-3).

<Step 4>
In a 300 mL three-neck flask, add about 7 g (about 22 mmol) of the 1,5-diamine derivative obtained in step 3.
-bis(2-fluorophenyl)-2,4-dihydroxybenzene, 13 g (96 mm
The flask was charged with 100 mL of potassium carbonate and 140 mL of N-methyl-2-pyrrolidinone, and the mixture was degassed by stirring while reducing the pressure inside the flask. After degassing, the system was emptied under a nitrogen stream, and the mixture was stirred at 200° C. for 7 hours.

After stirring, the mixture was allowed to cool to room temperature, and then toluene, water, and hydrochloric acid were added and stirred. The organic layer and the aqueous layer of the resulting mixture were separated, and the aqueous layer was extracted three times with toluene. The resulting extract and the organic layer were combined and washed with an aqueous sodium bicarbonate solution and saturated saline, and anhydrous magnesium sulfate was added for drying. The mixture was naturally filtered, and the filtrate was concentrated to obtain a yellow oily product. The obtained oily product was recrystallized with toluene/hexane to obtain the target white powdery solid.

The obtained solid was recrystallized with toluene/hexane to obtain the target solid. The recrystallization filtrate was concentrated to obtain an oily substance, which was purified by silica gel column chromatography (developing solvent: hexane) and recrystallized with hexane to obtain the target white powdery solid. The obtained white powdery solid was 2.2 g (8.5 mmol) in total, and the two fractions of Step 3 and Step 4 were
The synthesis method was obtained in a yield of 39% in this step. The synthesis scheme showing the above synthesis method is shown in the following formula (B-4).

<Step 5>
In a 200 mL three-neck flask, 2.2 g (8.5 mmol) of benzo[1,2-b:5,
The flask was then degassed by stirring while reducing the pressure in the flask. After degassing, the system was conditioned under a nitrogen stream, and 40 mL of dehydrated tetrahydrofuran was added. The resulting solution was stirred at −78° C.

After stirring, 5.6 mL of n-butyllithium hexane solution (1.60 mol/L, 9.0 m
At the same temperature, 2.20 g (8.7 mmol) of iodine was added dropwise, and the mixture was then warmed to room temperature and stirred for 30 minutes. After stirring, the resulting solution was cooled to -78°C, and a solution of 2.20 g (8.7 mmol) of iodine dissolved in 10 mL of dehydrated tetrahydrofuran was added dropwise at the same temperature. After the addition, the resulting solution was warmed to room temperature and stirred at the same temperature for about 15 hours.

After stirring, water was added to the resulting solution and stirred, and the resulting mixture was separated into an organic layer and an aqueous layer.
The aqueous layer obtained was extracted three times with toluene, and the resulting extract and the organic layer were combined and washed with an aqueous sodium hydrogen carbonate solution, an aqueous sodium thiosulfate solution, and then with saturated saline, and dried by adding anhydrous magnesium sulfate. The mixture obtained was naturally filtered, and the filtrate was concentrated to obtain a solid. The solid was recrystallized with toluene/hexane to obtain a light brown solid of 2.
The compound was obtained in an amount of 5 g (6.5 mmol) with a yield of 76%. The synthesis scheme showing the above synthesis method is shown in the following formula (B-5).

<Step 6>
In a 200 mL three-neck flask, 1.5 g (3.8 mmol) of 6-iodo-benzo[1,
2-b: 5,4-b']bisbenzofuran and 1.8 g (4.2 mmol) of 2-[3-
(2-dibenzo[f,h]quinoxalinyl)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 70 mg (0.23 mmol) of tris(2-methylphenyl)phosphine, 20 mL of toluene, 2 mL of ethanol, and 6 mL of an aqueous potassium carbonate solution (2.0 mol/L) were placed in the flask, and the mixture was stirred while reducing the pressure inside the flask, to degas the mixture.

After degassing, the system was purged with a nitrogen gas stream, and the mixture was heated to 80° C. After heating, 10 mg (
45 μmol) of palladium(II) acetate was added, and the mixture was stirred at the same temperature for 2.5 hours. After stirring, the mixture was allowed to cool to room temperature, and then 10 mg (45 μmol) of palladium(II) acetate was added again.
II) was added and stirred for 8 hours. After cooling to room temperature, the mixture was concentrated and diluted with 20 mL of ethylene glycol dimethyl ether and 6 mL of an aqueous solution of sodium carbonate (2.0 mol
1/L) was added, and the mixture was degassed by stirring while reducing the pressure inside the flask.

After degassing, the inside of the system was purged with a nitrogen gas flow and then heated to 80° C. After heating, 0.10 g (87 μ
mol) of tetrakis(triphenylphosphine)palladium(0) was added and stirred for 1.5 hours. After stirring, the resulting mixture was allowed to cool to room temperature, and the precipitated solid was collected by suction filtration. The resulting solid was washed with water and ethanol. The resulting solid was dissolved in toluene and filtered through celite and alumina. The filtrate was concentrated to obtain a solid, which was recrystallized with toluene to obtain 1.2 g (2.1 mmol) of a pale yellow solid, which was the target product, in a yield of 55%.

The obtained solid was purified by sublimation using a train sublimation method. The sublimation purification was performed by heating the solid at 310°C for 15.5 hours while flowing argon at a pressure of 2.5 Pa and a flow rate of 5 mL/min, and 0.90 g of the target pale yellow solid was obtained with a recovery rate of 75%. The synthesis scheme showing the above synthesis method is shown in the following formula (B-6).

The results of analysis of the pale yellow solid obtained by the above synthesis method by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) are shown below. The ¹ H-NMR chart is shown in Figure 17. From these results, it was found that in Synthesis Example 2, the heterocyclic compound 2mBbf(II)PDBq, which is one embodiment of the present invention and is represented by the above structural formula (107), was obtained.

¹ H NMR (tetrachloroethane-d ₂ , 500 MHz): δ=7.49 (t, J=8
.0 Hz, 2H), 7.56 (t, J = 8.0 Hz, 2H), 7.74 (d, J = 8.0
Hz, 2H), 7.81-7.89 (m, 4H), 7.93 (t, J = 8.0 Hz, 1H
), 8.18 (d, J = 7.5 Hz, 2H) 8.43 (d, J = 6.5 Hz, 1H), 8
． 53 (d, J = 8.0 Hz, 1H), 8.56 (s, 1H), 8.71 (d, J = 8.
0 Hz, 2H), 9.27 (s, 1H), 9.34 (d, J=7.5 Hz, 1H), 9.
56 (d, J = 8.0 Hz, 1H), 9.60 (s, 1H).

Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of the toluene solution and solid thin film of 2mBbf(II)PDBq were measured. The solid thin film was prepared on a quartz substrate by vacuum deposition. A UV-visible spectrophotometer (V550 type, manufactured by JASCO Corporation) was used to measure the absorption spectrum. A fluorometer (FS920, manufactured by Hamamatsu Photonics Corporation) was used to measure the emission spectrum. The measurement results of the absorption spectrum and emission spectrum of the obtained toluene solution are shown in FIG. 18(A). The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity. The measurement results of the absorption spectrum and emission spectrum of the solid thin film are shown in FIG. 18(B). The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity.

From the results of FIG. 18(A), in the toluene solution of 2mBbf(II)PDBq,
18(B), the solid thin film of 2mBbf(II)PDBq exhibited absorption peaks at 265 nm and 384 nm, and an emission wavelength peak at 430 nm.

Synthesis Example 3
In this example, a heterocyclic compound, 2-[3-(benzo[1,2-b:
A method for synthesizing [5,6-b']bisbenzofuran-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)PDBq) (structural formula (149)) will be described. The structure of 2mBbf(III)PDBq is shown below.

<Synthesis of 2mBbf(III)PDBq>
<Step 1>
In a 500 mL three-neck flask, 10 g (46 mmol) of 2-bromo-1,3-dimethoxybenzene, 7.2 g (51 mmol) of 2-fluorophenylboronic acid, and 66 mL
The flask was charged with toluene, 66 mL of diethylene glycol dimethyl ether (diglyme), and 76 mL of an aqueous solution of sodium carbonate (2.0 mol/L), and the mixture was degassed by stirring while reducing the pressure inside the flask. After degassing, the system was conditioned under a nitrogen gas flow, and the mixture was then stirred for 8 h.
The mixture was heated to 0° C. At the same temperature, 1.1 g (0.95 mmol) of tetrakis(
Tris(methylphenylphosphine)palladium(0) was added and the mixture was stirred for 5 hours.

After stirring, the resulting mixture was allowed to cool to room temperature, and then 3.2 g (23 mmol) of 2-fluorophenylboronic acid and 1.0 g (0.87 mmol) of tetrakis(trismethylphenylphosphine)palladium(0) were added, and the mixture was stirred while reducing the pressure inside the flask. The mixture was degassed, and the system was placed under a nitrogen stream, and the mixture was stirred at 80° C. for 8 hours. After stirring, the mixture was allowed to cool to room temperature, and then 5.2 g (37 mmol) of 2-fluorophenylboronic acid and 0.1
9 g (0.46 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl and 50 mg (0.22 mmol) of palladium(II) acetate were added, and the mixture was degassed by stirring while reducing the pressure inside the flask. After the system was purged with a nitrogen stream, the mixture was stirred at 80°C for 4 hours.

After stirring, the mixture was allowed to cool to room temperature and separated into an organic layer and an aqueous layer. The obtained aqueous layer was extracted three times with toluene, and the extract and the organic layer were combined and washed with saturated saline, and dried with anhydrous magnesium sulfate. The obtained mixture was naturally filtered, and the filtrate was concentrated to obtain a dark brown oily product. The obtained oily product was purified by silica gel column chromatography (the developing solvent was a gradient from hexane to chloroform), and then recrystallized with toluene/hexane, obtaining 8.4 g (36 mmol) of the target solid in a yield of 78%. The synthesis scheme showing the above synthesis method is shown in the following formula (C-1).

<Step 2>
In a 300 mL Erlenmeyer flask, 8.4 g (36 mmol) of 2'-fluoro-
1,3-Dimethoxy-2,1'-biphenyl and 130 mL of acetonitrile were added, and 6.4 g (36 mmol) of N-bromosuccinimide was added to the resulting solution, and the resulting solution was stirred at room temperature for 23.5 hours. After stirring, water and dichloromethane were added to the resulting solution, and the organic layer and the aqueous layer of this mixture were separated.

The aqueous layer was extracted three times with dichloromethane, and the resulting extract was combined with the organic layer, washed with a saturated aqueous sodium thiosulfate solution and saturated saline, and dried over anhydrous magnesium sulfate. The mixture was naturally filtered, and the filtrate was concentrated to obtain 11 g (35 mmol) of a yellow oil, which was the target product, in a yield of 97%. The synthesis scheme showing the above synthesis method is shown in the following formula (C-2).

<Step 3>
In a 300 mL three-neck flask, 11 g (35 mmol) of 4-bromo-2'-fluoro-
1,3-dimethoxy-2,1'-biphenyl was added, and the inside of the system was purged with a nitrogen gas stream.
51 g (37 mmol) of 3-chloro-2-fluoro-benzeneboronic acid, 55 mL of aqueous sodium carbonate solution (2.0 mol/L), 50 mL of toluene, 50 mL of ethylene glycol dimethyl ether, and 0.16 g (0.39 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl were added. The mixture was degassed by stirring while reducing the pressure inside the flask. After degassing, the system was placed under a nitrogen stream and heated to 80°C. Then, 40 mg (0.18 mmol) of palladium acetate (II) was added and stirred at the same temperature for 2 hours.

After stirring, the resulting mixture was allowed to cool to room temperature, and then 3.4 g (19 mmol) of 3-chloro-2-fluoro-benzeneboronic acid was added and heated to 80° C.
g (0.18 mmol) of palladium(II) acetate was added, and the mixture was stirred at the same temperature for 3 hours.
After stirring, 0.90 g (5.2 mmol) of 3-chloro-2-fluoro-benzeneboronic acid and 40 mg (0.18 mmol) of palladium(II) acetate were added and heated to 80° C., and the mixture was stirred for 7 hours. After stirring, the mixture was allowed to cool to room temperature, and then the organic layer and the aqueous layer were separated.
The aqueous layer was extracted three times with toluene, and the resulting extract and the organic layer were combined, washed with saturated saline, and dried over anhydrous magnesium sulfate. The filtrate obtained by gravity filtration was concentrated to obtain an oily product.

The oily product was purified by silica gel column chromatography (eluent: hexane:ethyl acetate 10:1) and recrystallized from toluene/hexane to obtain the target solid. The mother liquor of the recrystallization was concentrated to obtain a solid, which was purified by high performance liquid chromatography (eluent: chloroform) and recrystallized from toluene/hexane to obtain the target solid.
The target solid was obtained. The total amount of the target solid was 9.9 g (28 mmol), with a yield of 80%. The synthesis scheme showing the above synthesis method is shown in the following formula (C-3).

<Step 4>
Into a 500 mL three-neck flask, 9.8 g (27 mmol) of 4-(3-chloro-2-fluorophenyl)-2-(2-fluorophenyl)-1,3-dimethoxybenzene was placed.
The flask was purged with nitrogen and 150 mL of dehydrated dichloromethane was added. The resulting solution was placed in an ice bath and stirred, and 70 mL of boron tribromide (1 mol/L dichloromethane solution) was added.
A solution of L (70 mmol) diluted with 90 mL of dehydrated dichloromethane was dropped. After dropping, the obtained solution was stirred at room temperature for 15 hours. After stirring, the obtained solution was cooled in an ice bath, 20 mL of methanol was dropped, and 40 mL of water was further dropped. The organic layer and the aqueous layer of the obtained mixture were separated. The obtained aqueous layer was extracted three times with dichloromethane, and the extract and the organic layer were combined and washed with an aqueous sodium bicarbonate solution and saturated saline, and dried with anhydrous magnesium sulfate. A brown oily product was obtained by concentrating the filtrate obtained by natural filtration of the obtained mixture. The obtained oily product was purified by silica gel column chromatography (developing solvent was hexane:ethyl acetate 8:1) and then recrystallized with hexane/chloroform, and 8.7 g (26 mmol) of the target white solid was obtained in a yield of 96%. The synthesis scheme showing the above synthesis method is shown in the following formula (C-4).

<Step 5>
In a 500 mL recovery flask, 8.7 g (26 mmol) of 4-(3-chloro-2-fluorophenyl)-2-(2-fluorophenyl)-1,3-dihydroxybenzene and 14
The flask was charged with 1.0 g (0.10 mmol) of potassium carbonate and 150 mL of N-methyl-2-pyrrolidinone, and the mixture was degassed by stirring while reducing the pressure inside the flask. After degassing, the system was conditioned under a nitrogen gas flow, and the mixture was stirred at 200° C. for 9 hours. After stirring, the mixture was allowed to cool to room temperature, and then toluene, water, and hydrochloric acid were added and stirred, and the organic layer and aqueous layer of the resulting mixture were separated.

The aqueous layer obtained was extracted three times with toluene, and the resulting extract and the organic layer were combined, washed with an aqueous sodium bicarbonate solution and saturated saline, and dried with anhydrous magnesium sulfate. The mixture was naturally filtered, and the filtrate was concentrated to obtain a brown solid. The obtained solid was recrystallized with toluene/hexane to obtain 3.4 g (12 mmol) of the first crystal.
), and 1.6 g (5.4 mmol) of the second crystal were obtained, with the combined yield of the first and second crystals being 67%. The synthesis scheme showing the above synthesis method is shown in the following formula (C-5).

<Step 6>
In a 100 mL three-neck flask, 1.5 g (5.2 mmol) of 4-chlorobenzo[1,2
-b;5,6-b']bisbenzofuran and 2.5 g (5.7 mmol) of 2-[3-(
2-dibenzo[f,h]quinoxalinyl)phenyl]-4,4,5,5-tetramethyl-
1,3,2-dioxaborolane, 80 mg (0.22 mmol) of di(1-adamantyl)(n-butyl)phosphine, 1.5 mL (16 mmol) of t-butanol, and 3
6 g (17 mmol) of potassium phosphate (III) and 26 mL of diethylene glycol dimethyl ether (diglyme) were added, and the mixture was degassed by stirring while reducing the pressure in the flask. After degassing, the system was swept under nitrogen and the mixture was heated to 80°C.

To this mixture, 10 mg (45 μmol) of palladium(II) acetate was added, and the mixture was stirred at the same temperature for 4
The mixture was stirred for 3 hours. After stirring, the mixture was allowed to cool to room temperature, and then 10 mg (45 μmol) of palladium acetate (II) was added, and the mixture was stirred at 100° C. for 7 hours. After that, the mixture was allowed to cool to room temperature, and then 20 mg (89 μmol) of palladium acetate (II) was added, and the mixture was stirred at 120° C. for 4.5 hours. After stirring, the mixture was allowed to cool to room temperature, and then the precipitate was collected by suction filtration.

The obtained solid was washed with water and ethanol. The obtained solid was dissolved in toluene by heating, and the obtained solution was filtered through Celite and alumina. The obtained filtrate was concentrated to obtain a solid, which was recrystallized with toluene to obtain 1.4 g (2.4 mmol) of the target solid.
The yield was 46%.

The obtained solid was purified by train sublimation. The purification was carried out by heating the solid at 305°C for 20 hours under a pressure of 2.8 Pa and a flow rate of argon of 10 mL/min. After the purification by sublimation, 1.1 g of the target pale yellow solid was obtained with a recovery rate of 77%. The synthesis scheme showing the above synthesis method is shown in the following formula (C-6).

The results of analysis of the pale yellow solid obtained by the above synthesis method by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) are shown below. The ¹ H-NMR chart is shown in Figure 19. From these results, it was found that in Synthesis Example 3, the heterocyclic compound 2mBbf(III)PDBq, which is one embodiment of the present invention and is represented by the above structural formula (149), was obtained.

¹ H NMR (tetrachloroethane-d ₂ , 500 MHz): δ=7.29 (t, J=7
． 5Hz, 1H), 7.50 (t, J = 7.5Hz, 1H), 7.62-7.73 (m,
4H), 7.80-7.89 (m, 4H), 7.92 (t, J = 7.5 Hz, 1H), 8
． 12 (d, J = 7.5 Hz, 1H), 8.15 (d, J = 8.5 Hz, 1H), 8.2
9 (d, J = 7.5 Hz, 2H), 8.54 (d, J = 8.0 Hz, 1H), 8.70 (
t, J = 8.0 Hz, 2H), 9.15 (s, 1H), 9.36 (d, J = 7.5 Hz,
1H), 9.48 (d, J=7.5 Hz, 1H), 9.65 (s, 1H).

Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of the toluene solution and solid thin film of 2mBbf(III)PDBq were measured. The solid thin film was prepared on a quartz substrate by vacuum deposition. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (V550 type, manufactured by JASCO Corporation). The emission spectrum was measured using a fluorometer (FS920, manufactured by Hamamatsu Photonics Corporation). The measurement results of the absorption spectrum and emission spectrum of the obtained toluene solution are shown in FIG. 20(A). The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity. The measurement results of the absorption spectrum and emission spectrum of the solid thin film are shown in FIG. 20(B). The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity.

From the results of FIG. 20(A), in the toluene solution of 2mBbf(III)PDBq, 281n
Absorption peaks were observed at around 376 nm and 394 nm, and emission wavelength peaks were observed at around 407 nm.
In the solid thin film of q, absorption peaks were observed near 266 nm and 384 nm, and an emission wavelength peak was observed near 429 nm.

Synthesis Example 4
In this example, a heterocyclic compound, 2-[3′-(benzo[1,2-b
2mBbf(III)BPDBq (structural formula (1
The synthesis method of 2mBbf(III)BPDBq is shown below.

<Synthesis of 2mBbf(III)BPDBq>
<Step 1>
In a 200 mL three-neck flask, 1.5 g (2.8 mmol) of 4-chlorobenzo[1,2
-b;5,6-b']bisbenzofuran and 1.4 g (3.2 mmol) of 2-[3'-
(2-dibenzo[f,h]quinoxalinyl)-1,1'-biphenyl-3-yl]-4,
4,5,5-tetramethyl-1,3,2-dioxaborolane and 60 mg (0.17 mm
1.5 g (5.2 mmol) of di(1-adamantyl)(n-butyl)phosphine, 1 mL of t-butanol, 1.7 g (8.2 mmol) of potassium phosphate(III), and 15 mL of diethylene glycol dimethyl ether (diglyme) were placed in the flask, and the mixture was degassed by stirring while reducing the pressure inside the flask.

After degassing, the system was purged with a nitrogen gas stream, and the mixture was heated to 80° C. After heating, 10 mg (45 μmol) of palladium (II) acetate was added to the mixture, and the mixture was stirred at the same temperature for 6 hours. After stirring, the resulting mixture was allowed to cool to room temperature, and then 10 mg (45 μmol) of palladium (II) acetate was added, and the mixture was stirred at 120° C. for 4.5 hours, and then at 140° C. for 3 hours.
After stirring, the mixture was allowed to cool to room temperature, and the precipitated solid was collected by suction filtration. The obtained solid was washed with water and ethanol, and 1.6 g (2.4 mmol) of a light brown solid, which was the target product, was obtained.
l) was obtained in a yield of 86%.

The obtained solid (1.49 g) was purified by train sublimation. The purification was carried out by heating the solid at 350° C. under a pressure of 5.1 Pa and a flow rate of argon of 15 mL/min.
After purification by sublimation, 1.1 g of the target pale yellow solid was obtained, with a recovery rate of 76%.
The synthesis scheme showing the above synthesis method is shown in the following formula (D-1).

The results of analysis of the pale yellow solid obtained by the above synthesis method by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) are shown below. The ¹ H-NMR chart is shown in Figure 21. From these results, it was found that in Synthesis Example 4, the heterocyclic compound 2mBbf(III)BPDBq, which is one embodiment of the present invention and is represented by the above structural formula (150), was obtained.

¹ H NMR (tetrachloroethane-d ₂ , 500 MHz): δ=7.20 (t, J=7
． 5Hz, 1H), 7.31 (t, J=7.5Hz, 1H), 7.50 (d, J=7.5
Hz, 1H), 7.58 (t, J = 7.5 Hz, 2H), 7.65 (d, J = 7.5 Hz
, 1H), 7.75-7.84 (m, 6H), 7.93 (d, J = 7.5 Hz, 1H),
8.03 (d, J = 7.5 Hz, 1H), 8.07 (d, J = 7.5 Hz, 1H), 8.
12 (t, J = 7.5 Hz, 2H), 8.20 (d, J = 7.5 Hz, 1H), 8.38
(d, J = 7.5 Hz, 1H), 8.62-8.66 (m, 3H), 8.82 (s, 1H
), 9.27 (d, J = 7.5 Hz, 1H), 9.32 (d, J = 7.5 Hz, 1H),
9.49 (s, 1H).

Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of the toluene solution and solid thin film of 2mBbf(III)BPDBq were measured. The solid thin film was prepared on a quartz substrate by vacuum deposition. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (V550 model, manufactured by JASCO Corporation). The emission spectrum was measured using
A fluorometer (FS920, manufactured by Hamamatsu Photonics K.K.) was used. The results of measuring the absorption spectrum and emission spectrum of the obtained toluene solution are shown in FIG. 22(A). The horizontal axis represents wavelength, and the vertical axis represents absorption intensity. The results of measuring the absorption spectrum and emission spectrum of the solid thin film are shown in FIG. 22(B). The horizontal axis represents wavelength, and the vertical axis represents absorption intensity.

From the results of FIG. 22(A), in the toluene solution of 2mBbf(III)BPDBq, 264
Absorption peaks were observed at around 385 nm and 391 nm, and emission wavelength peaks were observed at around 407 nm.
In the solid thin film of DBq, absorption peaks are observed around 264 nm and 385 nm, and
A peak in the emission wavelength was observed around m.

In this example, a heterocyclic compound according to one embodiment of the present invention, 2mBbfPDBq (structural formula (10
Light-emitting device 1 using 2mBbf(II)PDBq (structural formula (107)), light-emitting device 2 using 2mBbf(III)PDBq (structural formula (149)),
A light-emitting element 4 was fabricated using 2mBbf(III)BPDBq (structural formula (150)).
A comparative light-emitting element 5 was manufactured using II. Note that the manufacture of the light-emitting elements 1 to 4 and the comparative light-emitting element 5 will be described with reference to Fig. 23. The chemical formulae of materials used in this example are shown below.

<Fabrication of Light-emitting Elements 1 to 4 and Comparative Light-emitting Elements 5>
First, indium tin oxide (ITO) containing silicon oxide was formed by sputtering on a glass substrate 900 to form a first electrode 901 functioning as an anode. The thickness of the electrode was 110 nm, and the area of the electrode was 2 mm×2 mm.

Next, as a pretreatment for forming the light emitting element 1 on the substrate 900, the substrate surface was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

Thereafter, the substrate is introduced into a vacuum deposition apparatus whose inside has been reduced in pressure to about 10 ⁻⁴ Pa, and vacuum baking is performed at 170° C. for 30 minutes in a heating chamber in the vacuum deposition apparatus.
It was left to cool for about minutes.

Next, the substrate 900 was fixed to a holder provided in a vacuum deposition apparatus so that the surface on which the first electrode 901 was formed faced downward. In this example, a case will be described in which a hole injection layer 911, a hole transport layer 912, a light emitting layer 913, an electron transport layer 914, and an electron injection layer 915, which constitute an EL layer 902, are successively formed by vacuum deposition.

After reducing the pressure in the vacuum chamber to 10 ⁻⁴ Pa, 1,3,5-tri(dibenzothiophene-4-
DBT3P-II:
The hole injection layer 911 was formed on the first electrode 901 by co-evaporation so that the ratio of molybdenum oxide to molybdenum oxide was 4:2 (mass ratio). The film thickness was 20 nm. Note that co-evaporation is a deposition method in which a plurality of different substances are simultaneously evaporated from different evaporation sources.

Next, 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) was evaporated to a thickness of 20 nm to form a hole transporting layer 912 .

Next, the light-emitting layer 913 was formed on the hole transport layer 912.

In the case of the light-emitting element 1, 2-[3-(benzo[1,2-b:4,5-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbfPDBq
), N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluoren-2-amine (
Abbreviated name: PCBBiF), [Ir(tBuppm) ₂ (acac)], 2mBbfPDB
q: PCBBiF: [Ir (tBuppm) ₂ (acac)] = 0.7: 0.3: 0.0
The mixture was co-deposited so that the mass ratio of the mixture was 5.5. The film thickness was 20 nm.
2mBbfPDBq:PCBBiF:[Ir(tBuppm) ₂ (acac)]=0.8
: 0.2:0.05 (mass ratio) and a thickness of 20 nm was formed, whereby a light emitting layer 913 having a stacked structure was formed to a thickness of 40 nm.

In the case of the light-emitting element 2, 2-[3-(benzo[1,2-b:5,4-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(II)
PDBq), PCBBiF, [Ir(tBuppm) ₂ (acac)], 2mBbf (
II) PDBq:PCBBiF:[Ir(tBuppm) ₂ (acac)]=0.7:0
3:0.05 (mass ratio) to form a film having a thickness of 20 nm.
bf(II)PDBq:PCBBiF:[Ir(tBuppm) ₂ (acac)]=0.
The light emitting layer 913 having a stacked structure was formed to a thickness of 40 nm by co-evaporation so as to have a mass ratio of 8:0.2:0.05 and a thickness of 20 nm.

In the case of the light-emitting element 3, 2-[3-(benzo[1,2-b:5,6-b']bisbenzofuran-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III
) PDBq), PCBBiF, [Ir(tBuppm) ₂ (acac)], 2mBbf
(III) PDBq:PCBBiF:[Ir(tBuppm) ₂ (acac)]=0.7
0.3:0.05 (mass ratio) to form a 20 nm thick film.
mBbf(III)PDBq:PCBBiF:[Ir(tBuppm) ₂ (acac)]
= 0.8:0.2:0.05 (mass ratio) and a thickness of 20 nm were formed, whereby a light emitting layer 913 having a stacked structure was formed to a thickness of 40 nm.

In the case of the light-emitting element 4, 2-[3′-(benzo[1,2-b:5,6-b′]bisbenzofuran-4-yl)-1,1′-biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)BPDBq), PCBBiF, [Ir(tBuppm) ₂
(acac)] to 2mBbf(III)BPDBq:PCBBiF:[Ir(tBup
pm) ₂ (acac)] = 0.7:0.3:0.05 (mass ratio),
After forming a film having a thickness of 20 nm, 2mBbf(III)BPDBq:PCBBiF:[Ir
(tBuppm) ₂ (acac) = 0.8:0.2:0.05 (mass ratio) to form a light emitting layer 913 having a stacked structure with a thickness of 40 nm.
The film was formed to a thickness of .

In the case of the comparative light-emitting element 5, 2-[3′-(dibenzothiophen-4-yl)biphenyl-
3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), P
CBBiF, [Ir(tBuppm) ₂ (acac)], 2mDBTBPDBq-II
: PCBBiF: [Ir (tBuppm) ₂ (acac)] = 0.7: 0.3: 0.05
(mass ratio) to form a film having a thickness of 20 nm.
-II: PCBBiF: [Ir (tBuppm) ₂ (acac)] = 0.8: 0.2: 0
The light-emitting layer 913 having a stacked structure was formed to a thickness of 40 nm by co-evaporation so that the ratio of the mixture to the total weight of the layers was 20 nm.

Next, on the light-emitting layer 913, 2mBbfPDBq was deposited to a thickness of 20 nm in the case of the light-emitting element 1, and then Bphen was deposited to a thickness of 10 nm. In the case of the light-emitting element 2, 2mBbf(II)PDBq was deposited to a thickness of 20 nm.
After the deposition of 10 nm, Bphen was deposited at 10 nm.
) After depositing PDBq to a thickness of 20 nm, Bphen was deposited to a thickness of 10 nm.
mBbf(III)BPDBq was evaporated to a thickness of 20 nm, and then Bphen was evaporated to a thickness of 10 nm to form an electron transport layer 914 .

Further, lithium fluoride was evaporated to a thickness of 1 nm on the electron transport layer 914 of each of the light-emitting elements 1 to 4 to form an electron injection layer 915 .

Finally, aluminum was evaporated on the electron injection layer 915 to a thickness of 200 nm to form a second electrode 903 serving as a cathode, thereby obtaining the light-emitting elements 1 to 4. Note that in all of the evaporation processes described above, evaporation was performed using a resistance heating method.

Table 1 shows the element structures of the thus obtained light-emitting elements 1 to 4 and the comparative light-emitting element 5.

The fabricated light-emitting elements 1 to 4 and the comparative light-emitting element 5 were sealed in a glove box with a nitrogen atmosphere so as not to be exposed to the air (a sealant was applied around the elements, and UV treatment was performed during sealing, and heat treatment was performed at 80° C. for 1 hour).

<Operation Characteristics of Light-Emitting Element 1 to Light-Emitting Element 4 and Comparative Light-Emitting Element 5>
The operation characteristics of the fabricated light-emitting elements 1 to 4 were measured.
The experiment was carried out in an atmosphere maintained at 5°C.

FIG. 24 shows current density-luminance characteristics of Light-emitting Elements 1 to 4, FIG. 25 shows voltage-luminance characteristics, FIG. 26 shows luminance-current efficiency characteristics, and FIG. 27 shows voltage-current characteristics.

Table 2 below shows main initial characteristic values of the light-emitting element 1, the light-emitting element 2, the light-emitting element 3, the light-emitting element 4, and the comparative light-emitting element 5 at around 1000 cd ^/ m2. Note that the comparative light-emitting element 5 was confirmed to have good initial characteristics comparable to those of the light-emitting elements 1 to 4.

28 shows emission spectra when a current density of 25 mA/cm ² is applied to the light-emitting elements 1 to 4. As shown in FIG. 28, the emission spectra of the light-emitting elements 1 to 4 have a peak at about 546 nm, which suggests that this is due to the green emission of the organometallic complex [Ir(tBuppm) ₂ (acac)] used in the EL layer of each light-emitting element. Note that the comparative light-emitting element 5 also has an emission spectrum of [Ir(tBu
An emission spectrum derived from the green emission of [C10(1,2-dichlorophenyl)phenyl] ( _{at 1,2-} dichlorophenyl)-2,3-tetrahydrofuran (C10( ...

Next, reliability tests were performed on the light-emitting elements 1 to 4. The results of the reliability tests are shown in FIG.
29. In FIG. 29, the vertical axis indicates normalized luminance (%) when the initial luminance is 100%, and the horizontal axis indicates the driving time (h) of the element.
/m ² , and the light-emitting elements 1 to 4 were driven under the condition of a constant current density.

Note that all of the light-emitting elements 1 to 4 use the heterocyclic compound which is one embodiment of the present invention, and the results shown in Fig. 29 show that all of the light-emitting elements have high reliability. This shows that the use of the heterocyclic compound which is one embodiment of the present invention can increase the lifetime of the light-emitting element.

In addition, a storage test was performed on the light-emitting elements 1 to 3 and the comparative light-emitting element 5.
Each light-emitting device was stored in a thermostatic chamber maintained at 100° C. without being driven, and after a predetermined time had passed, the operating characteristics were measured.
The experiment was carried out in an atmosphere maintained at 0.4 °C.

30 shows the measurement results of the external quantum efficiency over time for the light-emitting elements 1 to 3 and the comparative light-emitting element 5. As a result, it was revealed that the light-emitting elements 1 to 3, which are one embodiment of the present invention, can maintain their initial external quantum efficiency and good heat resistance even when stored for a long time at 100° C. In contrast, the comparative light-emitting element 5 showed a significant decrease in external quantum efficiency after about 10 hours.

In addition, 2mBbfPDBq used in the light-emitting element 1 and 2mBbf(II) used in the light-emitting element 2
Both the 2mBbf(III)PDBq used in the light-emitting element 3 and the 2mBbf(III)PDBq used in the light-emitting element 4 have a molecular weight of 562.
The molecular weight of 2mDBTBPDBq-II used in the comparative light-emitting element 5 is 564.
That is, although the light-emitting elements used in the storage test all had approximately the same molecular weight, a large difference in heat resistance in the 100° C. storage test was observed between the light-emitting elements 1 to 3 and the comparative light-emitting element 5.

Among the light-emitting elements 1 to 3 and the comparative light-emitting element 5, the light-emitting elements 1 to 3 have a molecular structure characteristic of having a fused aromatic ring, benzobisbenzofuran. The difference in heat resistance observed in the storage test is due to this molecular structure, and it has been shown that a compound and a light-emitting element having extremely high heat resistance can be obtained without increasing the molecular weight, making it clear that the use of a fused ring is very effective.

In this example, a heterocyclic compound according to one embodiment of the present invention, 2-[
HOMO levels and LU of 3-(benzo[1,2-b:4,5-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbfPDBq)
The MO level was calculated based on cyclic voltammetry (CV) measurements. The calculation method is shown below.

The measurement device used was an electrochemical analyzer (manufactured by BAS Co., Ltd., model number: ALS model 600A or 600C). The solution used in the CV measurement was dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 227) as a solvent.
056) was used as the supporting electrolyte, and tetra-n-butylammonium perchlorate (n-Bu)
_4NClO4 ) (Tokyo Chemical Industry Co. _, Ltd., catalog number: T0836) at 100 mmol/L
The solution was dissolved in water to give a concentration of 1 mmol/L, and the measurement target was further dissolved in water to give a concentration of 2 mmol/L.
The auxiliary electrode was a platinum electrode (B.A.S. Co., Ltd., Pt
A counter electrode (5 cm) was used as the electrode, and an Ag/Ag ⁺ electrode (manufactured by BAS Co., Ltd., RE7 non-aqueous solvent reference electrode) was used as the reference electrode.
5°C). The scan rate during CV measurement was standardized to 0.1 V/sec, and the oxidation potential Ea [V] and reduction potential Ec [V] relative to the reference electrode were measured. Ea was the midpoint potential of the oxidation-reduction wave, and Ec was the midpoint potential of the reduction-oxidation wave. Here, since the potential energy of the reference electrode used in this example relative to the vacuum level is known to be -4.94 [eV], HOMO level [eV] = -4.94 - Ea, LUMO level [eV]
The HOMO level and the LUMO level can be calculated from the formula: =-4.94-Ec. In addition, the CV measurement was repeated 100 times, and the oxidation-reduction wave in the 100th cycle was compared with the oxidation-reduction wave in the 1st cycle to examine the electrical stability of the compound.

As a result, in the measurement of the oxidation potential Ea [V] of 2 mBbfPDBq,
No clear oxidation peak was obtained in the range of 1.5 eV to 1.5 eV. On the other hand, the LUMO level was found to be −2.97 eV. In addition, in repeated measurements of the oxidation-reduction wave,
The oxidation-reduction wave after the 0th cycle maintained 73% of the peak intensity compared to the oxidation-reduction wave in the 1st cycle, confirming that the resistance to the reduction of 2mBbfPDBq was very good.

In addition, thermogravimetry-differential thermal analysis (TG-DTA) of 2 mBbfPDBq
The measurements were performed using a high vacuum differential thermobalance (T
The measurement was performed under normal pressure, a temperature rise rate of 10°C/min, and a nitrogen gas flow (flow rate: 200mL/min). From the relationship between weight and temperature (thermogravimetry),
The 5% weight loss temperature of 2mBbfPDBq was about 442°C.
It was demonstrated that fPDBq has good heat resistance.

Differential scanning calorimetry (DSC) was performed using a PerkinElmer Pyris 1 DSC.
The differential scanning calorimetry was performed at a temperature rise rate of 50°C/min from -10°C to 3°C.
After heating to 70°C, the temperature was kept for 1 minute, and then cooled to -10°C at a rate of 50°C/min.
The cooling operation was performed twice in succession to 20°C, and the second measurement result was adopted.
It was revealed that the glass transition temperature of mBbfPDBq was 147° C., making it a compound with high heat resistance.

Next, the 2mBbfPDBq obtained in this example was analyzed by liquid chromatography mass spectrometry (LCMS).
Chromatography Mass Spectrometry, abbreviation: L
The mixture was analyzed by HPLC (C/MS analysis).

For the LC/MS analysis, LC (liquid chromatography) separation was performed using Waters Acquis
Mass spectrometry (MS) was performed using a Waters Xevo HPLC (registered trademark).
The LC separation was performed using an Acquity UPL column.
C BEH C8 (2.1×100 mm 1.7 μm), column temperature was 40° C.
The mobile phase A was acetonitrile, and the mobile phase B was a 0.1% formic acid aqueous solution. The sample was prepared by dissolving 2mBbfPDBq of an arbitrary concentration in N-methyl-2-pyrrolidone and diluting with acetonitrile, and the injection volume was 5.0 μL.

A gradient method in which the composition of the mobile phase is changed was used for LC separation, with the ratio of mobile phase A:mobile phase B being 65:35 from 0 to 1 minute after the start of measurement, and the composition was then changed so that the ratio of mobile phase A to mobile phase B at 10 minutes after the start of measurement was 95:5, with the total analysis time being 10 minutes. The composition was changed linearly.

In the MS analysis, electrospray ionization was used.
Ionization was performed using electrospray ionization (ESI), with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range of the measurement was m/z = 100 to 1200.

When LC-MS measurement was performed under the above conditions, the ions derived from 2mBbfPDBq were
Mass-to-charge ratio (m/z) = 563.175 ([M+H ⁺ ], theoretical value of 2 mBbfPDBq =
The precursor ions were detected at a mass-to-charge ratio (m/z) of 563.175 (precursor ions). The precursor ions were then collided with argon gas in a collision cell to cause dissociation. The energy (collision energy) used to collide the precursor ions with argon was 50 eV and 70 eV. The product ions generated by the collision of the precursor ions with argon gas were detected by a time-of-flight (TOF) detector. A mass spectrum with a collision energy of 50 eV is shown in FIG. 31, and a mass spectrum with a collision energy of 70 eV is shown in FIG. 32.

From the results of FIG. 31, 2mBbfPDBq represented by structural formula (101) is mainly
m = 536.165, m / z = 345.091, m / z = 334.098,
It was found that product ions were detected near m/z = 305.096, near m/z = 229.076, near m/z = 202.066, and near m/z = 177.070.
From the results of FIG. 32, in the measurement with a collision energy of 70 eV, 2mBbfPDBq represented by structural formula (101) mainly exhibited peaks near m/z = 305.096 and m/z = 229.
It was found that product ions were detected at around m/z = 077, around m/z = 202.066, and around m/z = 176.063.
Since this shows a characteristic result derived from DBq, the 2mBb contained in the mixture
This can be said to be important data for identifying fPDBq.

The product ion at m/z=536.165 is presumed to be a structure generated by cleavage of the nitrogen-containing ring of dibenzo[f,h]quinoxaline in the compound of structural formula (101) as shown in the following formula (a). The product ion at m/z=345.091 is presumed to be a structure generated by cleavage of the nitrogen-containing ring of dibenzo[f,h]quinoxaline in the compound of structural formula (101) as shown in the following formula (b).
The product ion at m/z = 334.098 is presumed to be derived from 6-phenylbenzo[1,2-b:4,5-b']bisbenzofuran produced by cleavage of the bond at the 2-position of dibenzo[f,h]quinoxaline in the compound of structural formula (101) as shown in the following formula (c), and the product ion at m/z = 305.096 is presumed to be derived from benzo[1,2-b:4,5-b']bisbenzofuran produced by cleavage of the bond at the 2-position of dibenzo[f,h]quinoxaline in the compound of structural formula (101) as shown in the following formula (d).
2-Phenyldibenzo[f,h] is produced by cleavage of the bond at the 6-position of bisbenzofuran.
The product ion at around m/z = 229.076 is presumed to be derived from dibenzo[f,h]quinoxaline generated by cleavage of the bond at the 2-position of dibenzo[f,h]quinoxaline in the compound of structural formula (101) as shown in formula (e) below. The product ion at around m/z = 202.066 is presumed to be an ion generated by further cleavage of the product ion at around m/z = 536.165 as shown in formula (f) below. The product ion at around m/z = 177.070 is presumed to be an ion generated by further cleavage of the product ion at around m/z = 536.165 as shown in formula (g) below. In particular, the ions represented by formula (a), which is an ion generated by cleavage of a ring containing two nitrogen atoms in dibenzo[f,h]quinoxaline in the compound of structural formula (101), and the ions represented by formulas (b) to (d), which are ions generated by cleavage of a bond between the rings, are 2mBbfP
This is one of the characteristics of DBq and can be said to be important data for identifying 2mBbfPDBq contained in a mixture.

In this example, a heterocyclic compound according to one embodiment of the present invention, 2-[
The HOMO and LUMO levels of 3-(benzo[1,2-b:5,4-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(II)PDBq) were calculated based on cyclic voltammetry (CV) measurements. The calculation method is shown below.

The HOMO and LUMO levels of 2mBbf(II)PDBq were calculated based on cyclic voltammetry (CV) measurements.
The method of calculating the level is the same as in the sixth embodiment.

As a result, in the measurement of the oxidation potential Ea [V] of 2mBbf(II)PDBq, no clear oxidation peak was obtained in the measurement range from −0.2 eV to 1.5 eV.
The MO level was found to be -2.94 eV. In addition, in the repeated measurement of the oxidation-reduction wave, the oxidation-reduction wave after 100 cycles was 87 times higher than that of the first cycle.
%, it was confirmed that the resistance to reduction of 2mBbf(II)PDBq was very good.

Further, thermogravimetry-differential thermal analysis of 2mBbf(II)PDBq was carried out. The analysis method was the same as in Example 6. From the measurement results, it was found that the 5% weight loss temperature of 2mBbf(II)PDBq was about 459°C. This demonstrated that 2mBbf(II)PDBq has good heat resistance.

In this example, a heterocyclic compound according to one embodiment of the present invention, 2-[
The HOMO and LUMO levels of 3-(benzo[1,2-b:5,6-b']bisbenzofuran-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)PDBq) were calculated based on cyclic voltammetry (CV) measurements. The calculation method is shown below.

The HOMO and LUMO levels of 2mBbf(III)PDBq were calculated based on cyclic voltammetry (CV) measurements.
The method of calculating the O level is the same as in the sixth embodiment.

As a result, in the measurement of the oxidation potential Ea [V] of 2mBbf(III)PDBq, no clear oxidation peak was obtained in the measurement range from 0 eV to 1.5 eV.
The O level was found to be -2.95 eV. In addition, in the repeated measurement of the oxidation-reduction wave, the oxidation-reduction wave after 100 cycles was 79% lower than that of the first cycle.
It was confirmed that the peak intensity of 2mBbf(III)PDBq was very good against reduction.

Further, thermogravimetry-differential thermal analysis of 2mBbf(III)PDBq was carried out. The analysis method was the same as in Example 6. From the measurement results, the 5% weight loss temperature of 2mBbf(III)PDBq was about 454° C., which showed that 2mBbf(III)PDBq has good heat resistance.

In this example, a heterocyclic compound according to one embodiment of the present invention, 2-[
3'-(benzo[1,2-b:5,6-b']bisbenzofuran-4-yl)-1,1'
-biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III
The HOMO and LUMO levels of BPDBq were measured by cyclic voltammetry (CV
The calculation method is shown below.

The HOMO and LUMO levels of 2mBbf(III)BPDBq were calculated based on cyclic voltammetry (CV) measurements.
The calculation method of the MO level is the same as in Example 6.

As a result, in the measurement of the oxidation potential Ea [V] of 2mBbf(III)BPDBq, no clear oxidation peak was obtained in the measurement range of 0.1 eV to 1.5 eV. On the other hand, the LUMO level was found to be -2.98 eV. In addition, in the repeated measurement of the oxidation-reduction wave, the oxidation-reduction wave after 100 cycles maintained 71% of the peak intensity compared to the oxidation-reduction wave in the first cycle, confirming that 2mBbf(III)BPDBq has very good resistance to reduction.

101 First electrode 102 EL layer 103 Second electrode 111 Hole injection layer 112 Hole transport layer 113 Light-emitting layer 114 Electron transport layer 115 Electron injection layer 201 First electrode 202(1) First EL layer 202(2) Second EL layer 202(n-1) (n-1)th EL layer 202(n) (n)th EL layer 204 Second electrode 205 Charge generation layer 205(1) First charge generation layer 205(2) Second charge generation layer 205(n-2) (n-2)th charge generation layer 205(n-1) (n-1)th charge generation layer 301 Element substrate 302 Pixel section 303 Drive circuit section (source line drive circuit)
304a, 304b Drive circuit section (gate line drive circuit)
305 sealing material 306 sealing substrate 307 wiring 308 FPC (flexible printed circuit)
309 FET
310 FET
312 Current control FET
313a, 313b First electrode (anode)
314 Insulator 315 EL layer 316 Second electrode (cathode)
317a, 317b Light-emitting element 318 Space 320a, 320b Conductive film 321, 322 Region 323 Lead wiring 324 Color layer (color filter)
325 Black layer (black matrix)
326, 327, 328 FETs
401 Substrate 402 First electrode 404 Second electrode 403a, 403b, 403c EL layer 405 Light-emitting element 406 Insulating film 407 Partition wall 900 Substrate 901 First electrode 902 EL layer 903 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Light-emitting layer 914 Electron transport layer 915 Electron injection layer 2000 Touch panel 2501 Display panel 2502R Pixel 2502t Transistor 2503c Capacitor element 2503g Scanning line driver circuit 2503t Transistor 2509 FPC
2510 Substrate 2511 Wiring 2519 Terminal 2521 Insulating layer 2528 Insulator 2550R Light-emitting element 2560 Sealing layer 2567BM Light-shielding layer 2567p Anti-reflection layer 2567R Colored layer 2570 Substrate 2590 Substrate 2591 Electrode 2592 Electrode 2593 Insulating layer 2594 Wiring 2595 Touch sensor 2597 Adhesive layer 2598 Wiring 2599 Terminal 2601 Pulse voltage output circuit 2602 Current detection circuit 2603 Capacitor 2611 Transistor 2612 Transistor 2613 Transistor 2621 Electrode 2622 Electrode 4000 Lighting device 4001 Substrate 4002 Light-emitting element 4003 Substrate 4004 Electrode 4005 EL layer 4006 Electrode 4007 Electrode 4008 Electrode 4009 Auxiliary wiring 4010 Insulating layer 4011 Sealing substrate 4012 Sealing material 4013 Desiccant 4015 Diffusion plate 4100 Illumination device 4200 Illumination device 4201 Substrate 4202 Light-emitting element 4204 Electrode 4205 EL layer 4206 Electrode 4207 Electrode 4208 Electrode 4209 Auxiliary wiring 4210 Insulating layer 4211 Sealing substrate 4212 Sealing material 4213 Barrier film 4214 Planarization film 4215 Diffusion plate 4300 Illumination device 5101 Light 5102 Wheel 5103 Door 5104 Display unit 5105 Handle 5106 Shift lever 5107 Seat 5108 Inner rear view mirror 7100 Television device 7101 Housing 7103 Display unit 7105 Stand 7107 Display unit 7109 Operation keys 7110 Remote control device 7201 Main body 7202 Housing 7203 Display unit 7204 Keyboard 7205 External connection port 7206 Pointing device 7302 Housing 7304 Display unit 7305 Icon showing time 7306 Other icons 7311 Operation button 7312 Operation button 7313 Connection terminal 7321 Band 7322 Clasp 7400 Mobile phone 7401 Housing 7402 Display unit 7403 Operation button 7404 External connection unit 7405 Speaker 7406 Microphone 7407 Camera 7500 (1), 7500 (2) Housing 7501 (1), 7501 (2) First surface 7502 (1), 7502 (2) Second surface 8001 Illumination device 8002 Illumination device 8003 Illumination device 9310 Portable information terminal 9311 Display unit 9312 Display area 9313 Hinge 9315 Housing

Claims (5)

A heterocyclic compound represented by formula (G1):

(In the formula, DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group. When the arylene group has substituents, the substituents may be bonded to each other to form a ring.) A heterocyclic compound represented by formula (G1):

(In the formula, DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzobisbenzofuranyl group. Among the carbons not constituting a furan ring in the benzobisbenzofuranyl group, any one of the carbons adjacent to the carbon bonded to oxygen in the furan ring is bonded to Ar ^2. When the arylene group has substituents, the substituents may be bonded to each other to form a ring.) A heterocyclic compound represented by formula (G2):

(In the formula, A represents a substituted or unsubstituted benzobisbenzofuranyl group; R ¹ to R ⁹ each independently represent any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms; Ar ¹ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms; n represents 0 or 1; and Ar ² represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms. When the arylene group has substituents, the substituents may be bonded to each other to form a ring.) In any one of claims 1 to 3,
A in formula (G1) or formula (G2) is any one of the following formulas (A1) to (A3):
A heterocyclic compound represented by the following formulae (A1) to (A3), in which, among carbons not constituting a furan ring, any one of the carbons adjacent to the carbon bonded to oxygen in the furan ring is bonded to ^Ar2 .

(In the formula, the benzene ring may have a substituent, and the substituent is any one of a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 7 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 13 carbon atoms.) A heterocyclic compound represented by any one of formulas (101), (107), (149), and (150):

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